6 Jim Tcl v0.78+ - reference manual for the Jim Tcl scripting language
15 jimsh [<scriptfile>|-]
16 jimsh -e '<immediate-script>'
22 * <<CommandIndex,Command Reference>>
23 * <<OperatorPrecedence,Operator Precedence>>
24 * <<BuiltinVariables, Builtin Variables>>
25 * <<BackslashSequences, Backslash Sequences>>
29 Jim Tcl is a small footprint reimplementation of the Tcl scripting language.
30 The core language engine is compatible with Tcl 8.5+, while implementing
31 a significant subset of the Tcl 8.6 command set, plus additional features
32 available only in Jim Tcl.
34 Some notable differences with Tcl 8.5/8.6 are:
36 1. Object-based I/O (aio), but with a Tcl-compatibility layer
37 2. I/O: Support for sockets and pipes including udp, unix domain sockets and IPv6
39 4. Support for references (`ref`/`getref`/`setref`) and garbage collection
40 5. Builtin dictionary type (`dict`) with some limitations compared to Tcl 8.6
41 6. `env` command to access environment variables
42 7. Operating system features: `os.fork`, `os.uptime`, `wait`, `signal`, `alarm`, `sleep`
43 8. Much better error reporting. `info stacktrace` as a replacement for '$errorInfo', '$errorCode'
44 9. Support for "static" variables in procedures
45 10. Threads and coroutines are not supported
46 11. Command and variable traces are not supported
47 12. Built-in command line editing
48 13. Expression shorthand syntax: +$(...)+
49 14. Modular build allows many features to be omitted or built as dynamic, loadable modules
50 15. Highly suitable for use in an embedded environment
51 16. Support for UDP, IPv6, Unix-Domain sockets in addition to TCP sockets
57 1. Add `file mtimeus` for high resolution file timestamps
58 2. `aio` now supports datagram Unix-Domain sockets
59 3. Add support for `aio lock -wait`
61 Changes between 0.77 and 0.78
62 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
63 1. Add serial/tty support with `aio tty`
64 2. Add support for 'jimsh -'
65 3. Add hidden '-commands' option to many commands
66 4. Add scriptable autocompletion support in interactive mode with `tcl::autocomplete`
68 6. Add scriptable autocompletion support with `history completion`
69 7. Add support for `tree delete`
70 8. Add support for `defer` and '$jim::defer'
71 9. Renamed `os.wait` to `wait`, now more Tcl-compatible and compatible with `exec ... &`
72 10. `pipe` is now a synonym for `socket pipe`
73 11. Closing a pipe open with `open |...` now returns Tcl-like status
74 12. It is now possible to used `exec` redirection with a pipe opened with `open |...`
75 13. Interactive line editing now supports multiline mode if $::history::multiline is set
77 Changes between 0.76 and 0.77
78 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
79 1. Add support for `aio sync`
80 2. Add SSL and TLS support in aio
82 4. Added support for boolean constants in `expr`
83 5. `string is` now supports 'boolean' class
84 6. Add support for `aio lock` and `aio unlock`
85 7. Add new `interp` command
87 Changes between 0.75 and 0.76
88 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
89 1. `glob` now supports the +-tails+ option
90 2. Add support for `string cat`
91 3. Allow `info source` to add source info
93 Changes between 0.74 and 0.75
94 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
95 1. `binary`, `pack` and `unpack` now support floating point
96 2. `file copy` +-force+ handles source and target as the same file
97 3. `format` now supports +%b+ for binary conversion
98 4. `lsort` now supports +-unique+ and +-real+
99 5. Add support for half-close with `aio close` +?r|w?+
100 6. Add `socket pair` for a bidirectional pipe
101 7. Add '--random-hash' to randomise hash tables for greater security
102 8. `dict` now supports 'for', 'values', 'incr', 'append', 'lappend', 'update', 'info' and 'replace'
103 9. `file stat` no longer requires the variable name
104 10. Add support for `file link`
106 Changes between 0.73 and 0.74
107 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
108 1. Numbers with leading zeros are treated as decimal, not octal
110 3. Add LFS (64 bit) support for `aio seek`, `aio tell`, `aio copyto`, `file copy`
111 4. `string compare` and `string equal` now support '-length'
112 5. `glob` now supports '-directory'
114 Changes between 0.72 and 0.73
115 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
116 1. Built-in regexp now support non-capturing parentheses: (?:...)
117 2. Add `string replace`
118 3. Add `string totitle`
119 4. Add `info statics`
120 5. Add +build-jim-ext+ for easy separate building of loadable modules (extensions)
121 6. `local` now works with any command, not just procs
122 7. Add `info alias` to access the target of an alias
123 8. UTF-8 encoding past the basic multilingual plane (BMP) is supported
126 11. Most extensions are now enabled by default
127 12. Add support for namespaces and the `namespace` command
130 Changes between 0.71 and 0.72
131 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
132 1. procs now allow 'args' and optional parameters in any position
133 2. Add Tcl-compatible expr functions, `rand()`, `srand()` and `pow()`
134 3. Add support for the '-force' option to `file delete`
135 4. Better diagnostics when `source` fails to load a script with a missing quote or bracket
136 5. New +tcl_platform(pathSeparator)+
137 6. Add support settings the modification time with `file mtime`
138 7. `exec` is now fully supported on win32 (mingw32)
139 8. `file join`, `pwd`, `glob` etc. now work for mingw32
140 9. Line editing is now supported for the win32 console (mingw32)
141 10. Add `aio listen` command
143 Changes between 0.70 and 0.71
144 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
145 1. Allow 'args' to be renamed in procs
146 2. Add +$(...)+ shorthand syntax for expressions
147 3. Add automatic reference variables in procs with +&var+ syntax
148 4. Support +jimsh --version+
149 5. Additional variables in +tcl_platform()+
150 6. `local` procs now push existing commands and `upcall` can call them
151 7. Add `loop` command (TclX compatible)
152 8. Add `aio buffering` command
153 9. `info complete` can now return the missing character
154 10. `binary format` and `binary scan` are now (optionally) supported
155 11. Add `string byterange`
156 12. Built-in regexp now support non-greedy repetition (*?, +?, ??)
160 Tcl stands for 'tool command language' and is pronounced
161 'http://www.oxforddictionaries.com/definition/american_english/tickle[tickle]'.
162 It is actually two things: a language and a library.
164 First, Tcl is a simple textual language, intended primarily for
165 issuing commands to interactive programs such as text editors,
166 debuggers, illustrators, and shells. It has a simple syntax and is also
167 programmable, so Tcl users can write command procedures to provide more
168 powerful commands than those in the built-in set.
170 Second, Tcl is a library package that can be embedded in application
171 programs. The Tcl library consists of a parser for the Tcl language,
172 routines to implement the Tcl built-in commands, and procedures that
173 allow each application to extend Tcl with additional commands specific
174 to that application. The application program generates Tcl commands and
175 passes them to the Tcl parser for execution. Commands may be generated
176 by reading characters from an input source, or by associating command
177 strings with elements of the application's user interface, such as menu
178 entries, buttons, or keystrokes.
180 When the Tcl library receives commands it parses them into component
181 fields and executes built-in commands directly. For commands implemented
182 by the application, Tcl calls back to the application to execute the
183 commands. In many cases commands will invoke recursive invocations of the
184 Tcl interpreter by passing in additional strings to execute (procedures,
185 looping commands, and conditional commands all work in this way).
187 An application program gains three advantages by using Tcl for its command
188 language. First, Tcl provides a standard syntax: once users know Tcl,
189 they will be able to issue commands easily to any Tcl-based application.
190 Second, Tcl provides programmability. All a Tcl application needs
191 to do is to implement a few application-specific low-level commands.
192 Tcl provides many utility commands plus a general programming interface
193 for building up complex command procedures. By using Tcl, applications
194 need not re-implement these features.
196 Third, Tcl can be used as a common language for communicating between
197 applications. Inter-application communication is not built into the
198 Tcl core described here, but various add-on libraries, such as the Tk
199 toolkit, allow applications to issue commands to each other. This makes
200 it possible for applications to work together in much more powerful ways
201 than was previously possible.
203 Fourth, Jim Tcl includes a command processor, +jimsh+, which can be
204 used to run standalone Tcl scripts, or to run Tcl commands interactively.
206 This manual page focuses primarily on the Tcl language. It describes
207 the language syntax and the built-in commands that will be available
208 in any application based on Tcl. The individual library procedures are
209 described in more detail in separate manual pages, one per procedure.
211 JIMSH COMMAND INTERPRETER
212 -------------------------
213 A simple, but powerful command processor, +jimsh+, is part of Jim Tcl.
214 It may be invoked in interactive mode as:
218 or to process the Tcl script in a file with:
222 or to process the Tcl script from standard input:
226 It may also be invoked to execute an immediate script with:
232 Interactive mode reads Tcl commands from standard input, evaluates
233 those commands and prints the results.
236 Welcome to Jim version 0.73, Copyright (c) 2005-8 Salvatore Sanfilippo
239 . lsort [info commands p*]
240 package parray pid popen proc puts pwd
241 . foreach i {a b c} {
248 invalid command name "bad"
252 If +jimsh+ is configured with line editing (it is by default) and a VT-100-compatible
253 terminal is detected, Emacs-style line editing commands are available, including:
254 arrow keys, +\^W+ to erase a word, +\^U+ to erase the line, +^R+ for reverse incremental search
255 in history. Additionally, the +h+ command may be used to display the command history.
257 Command line history is automatically saved and loaded from +~/.jim_history+
259 In interactive mode, +jimsh+ automatically runs the script +~/.jimrc+ at startup
264 The central data structure in Tcl is an interpreter (C type 'Jim_Interp').
265 An interpreter consists of a set of command bindings, a set of variable
266 values, and a few other miscellaneous pieces of state. Each Tcl command
267 is interpreted in the context of a particular interpreter.
269 Some Tcl-based applications will maintain multiple interpreters
270 simultaneously, each associated with a different widget or portion of
271 the application. Interpreters are relatively lightweight structures.
272 They can be created and deleted quickly, so application programmers should
273 feel free to use multiple interpreters if that simplifies the application.
277 Tcl supports only one type of data: strings. All commands, all arguments
278 to commands, all command results, and all variable values are strings.
280 Where commands require numeric arguments or return numeric results,
281 the arguments and results are passed as strings. Many commands expect
282 their string arguments to have certain formats, but this interpretation
283 is up to the individual commands. For example, arguments often contain
284 Tcl command strings, which may get executed as part of the commands.
285 The easiest way to understand the Tcl interpreter is to remember that
286 everything is just an operation on a string. In many cases Tcl constructs
287 will look similar to more structured constructs from other languages.
288 However, the Tcl constructs are not structured at all; they are just
289 strings of characters, and this gives them a different behaviour than
290 the structures they may look like.
292 Although the exact interpretation of a Tcl string depends on who is doing
293 the interpretation, there are three common forms that strings take:
294 commands, expressions, and lists. The major sections below discuss
295 these three forms in more detail.
299 The Tcl language has syntactic similarities to both the Unix shells
300 and Lisp. However, the interpretation of commands is different
301 in Tcl than in either of those other two systems.
302 A Tcl command string consists of one or more commands separated
303 by newline characters or semi-colons.
304 Each command consists of a collection of fields separated by
305 white space (spaces or tabs).
306 The first field must be the name of a command, and the
307 additional fields, if any, are arguments that will be passed to
308 that command. For example, the command:
312 has three fields: the first, `set`, is the name of a Tcl command, and
313 the last two, 'a' and '22', will be passed as arguments to
314 the `set` command. The command name may refer either to a built-in
315 Tcl command, an application-specific command bound in with the library
316 procedure 'Jim_CreateCommand', or a command procedure defined with the
317 `proc` built-in command.
319 Arguments are passed literally as text strings. Individual commands may
320 interpret those strings in any fashion they wish. The `set` command,
321 for example, will treat its first argument as the name of a variable
322 and its second argument as a string value to assign to that variable.
323 For other commands arguments may be interpreted as integers, lists,
324 file names, or Tcl commands.
326 Command names should normally be typed completely (e.g. no abbreviations).
327 However, if the Tcl interpreter cannot locate a command it invokes a
328 special command named `unknown` which attempts to find or create the
331 For example, at many sites `unknown` will search through library
332 directories for the desired command and create it as a Tcl procedure if
333 it is found. The `unknown` command often provides automatic completion
334 of abbreviated commands, but usually only for commands that were typed
337 It's probably a bad idea to use abbreviations in command scripts and
338 other forms that will be re-used over time: changes to the command set
339 may cause abbreviations to become ambiguous, resulting in scripts that
344 If the first non-blank character in a command is +\#+, then everything
345 from the +#+ up through the next newline character is treated as
346 a comment and ignored. When comments are embedded inside nested
347 commands (e.g. fields enclosed in braces) they must have properly-matched
348 braces (this is necessary because when Tcl parses the top-level command
349 it doesn't yet know that the nested field will be used as a command so
350 it cannot process the nested comment character as a comment).
352 GROUPING ARGUMENTS WITH DOUBLE-QUOTES
353 -------------------------------------
354 Normally each argument field ends at the next white space, but
355 double-quotes may be used to create arguments with embedded space.
357 If an argument field begins with a double-quote, then the argument isn't
358 terminated by white space (including newlines) or a semi-colon (see below
359 for information on semi-colons); instead it ends at the next double-quote
360 character. The double-quotes are not included in the resulting argument.
361 For example, the command
363 set a "This is a single argument"
365 will pass two arguments to `set`: 'a' and 'This is a single argument'.
367 Within double-quotes, command substitutions, variable substitutions,
368 and backslash substitutions still occur, as described below. If the
369 first character of a command field is not a quote, then quotes receive
370 no special interpretation in the parsing of that field.
372 GROUPING ARGUMENTS WITH BRACES
373 ------------------------------
374 Curly braces may also be used for grouping arguments. They are similar
375 to quotes except for two differences. First, they nest; this makes them
376 easier to use for complicated arguments like nested Tcl command strings.
377 Second, the substitutions described below for commands, variables, and
378 backslashes do *not* occur in arguments enclosed in braces, so braces
379 can be used to prevent substitutions where they are undesirable.
381 If an argument field begins with a left brace, then the argument ends
382 at the matching right brace. Tcl will strip off the outermost layer
383 of braces and pass the information between the braces to the command
384 without any further modification. For example, in the command
386 set a {xyz a {b c d}}
388 the `set` command will receive two arguments: 'a'
391 When braces or quotes are in effect, the matching brace or quote need
392 not be on the same line as the starting quote or brace; in this case
393 the newline will be included in the argument field along with any other
394 characters up to the matching brace or quote. For example, the `eval`
395 command takes one argument, which is a command string; `eval` invokes
396 the Tcl interpreter to execute the command string. The command
403 will assign the value '22' to 'a' and '33' to 'b'.
405 If the first character of a command field is not a left
406 brace, then neither left nor right
407 braces in the field will be treated specially (except as part of
408 variable substitution; see below).
410 COMMAND SUBSTITUTION WITH BRACKETS
411 ----------------------------------
412 If an open bracket occurs in a field of a command, then command
413 substitution occurs (except for fields enclosed in braces). All of the
414 text up to the matching close bracket is treated as a Tcl command and
415 executed immediately. Then the result of that command is substituted
416 for the bracketed text. For example, consider the command
420 When the `set` command has only a single argument, it is the name of a
421 variable and `set` returns the contents of that variable. In this case,
422 if variable 'b' has the value 'foo', then the command above is equivalent
427 Brackets can be used in more complex ways. For example, if the variable
428 'b' has the value 'foo' and the variable 'c' has the value 'gorp',
431 set a xyz[set b].[set c]
433 is equivalent to the command
438 A bracketed command may contain multiple commands separated by newlines
439 or semi-colons in the usual fashion. In this case the value of the last
440 command is used for substitution. For example, the command
445 is equivalent to the command
450 If a field is enclosed in braces then the brackets and the characters
451 between them are not interpreted specially; they are passed through to
452 the argument verbatim.
454 VARIABLE SUBSTITUTION WITH $
455 ----------------------------
456 The dollar sign (+$+) may be used as a special shorthand form for
457 substituting variable values. If +$+ appears in an argument that isn't
458 enclosed in braces then variable substitution will occur. The characters
459 after the +$+, up to the first character that isn't a number, letter,
460 or underscore, are taken as a variable name and the string value of that
461 variable is substituted for the name.
463 For example, if variable 'foo' has the value 'test', then the command
467 is equivalent to the command
471 There are two special forms for variable substitution. If the next
472 character after the name of the variable is an open parenthesis, then
473 the variable is assumed to be an array name, and all of the characters
474 between the open parenthesis and the next close parenthesis are taken as
475 an index into the array. Command substitutions and variable substitutions
476 are performed on the information between the parentheses before it is
479 For example, if the variable 'x' is an array with one element named
480 'first' and value '87' and another element named '14' and value 'more',
483 set a xyz$x(first)zyx
485 is equivalent to the command
489 If the variable 'index' has the value '14', then the command
491 set a xyz$x($index)zyx
493 is equivalent to the command
497 For more information on arrays, see VARIABLES AND ARRAYS below.
499 The second special form for variables occurs when the dollar sign is
500 followed by an open curly brace. In this case the variable name consists
501 of all the characters up to the next curly brace.
503 Array references are not possible in this form: the name between braces
504 is assumed to refer to a scalar variable. For example, if variable
505 'foo' has the value 'test', then the command
509 is equivalent to the command
514 Variable substitution does not occur in arguments that are enclosed in
515 braces: the dollar sign and variable name are passed through to the
518 The dollar sign abbreviation is simply a shorthand form. +$a+ is
519 completely equivalent to +[set a]+; it is provided as a convenience
522 SEPARATING COMMANDS WITH SEMI-COLONS
523 ------------------------------------
524 Normally, each command occupies one line (the command is terminated by a
525 newline character). However, semi-colon (+;+) is treated as a command
526 separator character; multiple commands may be placed on one line by
527 separating them with a semi-colon. Semi-colons are not treated as
528 command separators if they appear within curly braces or double-quotes.
530 BACKSLASH SUBSTITUTION
531 ----------------------
532 Backslashes may be used to insert non-printing characters into command
533 fields and also to insert special characters like braces and brackets
534 into fields without them being interpreted specially as described above.
536 The backslash sequences understood by the Tcl interpreter are
537 listed below. In each case, the backslash
538 sequence is replaced by the given character:
539 [[BackslashSequences]]
550 Carriage-return (0xd).
573 +{backslash}<space>+::
574 Space ( ): doesn't terminate argument.
577 Semi-colon: doesn't terminate command.
582 +{backslash}<newline>+::
583 Nothing: this joins two lines together
584 into a single line. This backslash feature is unique in that
585 it will be applied even when the sequence occurs within braces.
587 +{backslash}{backslash}+::
588 Backslash ('{backslash}').
591 The digits +'ddd'+ (one, two, or three of them) give the octal value of
592 the character. Note that Jim supports null characters in strings.
595 +{backslash}u\{nnn\}+::
596 +{backslash}Unnnnnnnn+::
597 The UTF-8 encoding of the unicode codepoint represented by the hex digits, +'nnnn'+, is inserted.
598 The 'u' form allows for one to four hex digits.
599 The 'U' form allows for one to eight hex digits.
600 The 'u\{nnn\}' form allows for one to eight hex digits, but makes it easier to insert
601 characters UTF-8 characters which are followed by a hex digit.
603 For example, in the command
607 the second argument to `set` will be +{x[ yza+.
609 If a backslash is followed by something other than one of the options
610 described above, then the backslash is transmitted to the argument
611 field without any special processing, and the Tcl scanner continues
612 normal processing with the next character. For example, in the
617 The first argument to `set` will be +{backslash}*a+ and the second
618 argument will be +{backslash}{foo+.
620 If an argument is enclosed in braces, then backslash sequences inside
621 the argument are parsed but no substitution occurs (except for
622 backslash-newline): the backslash
623 sequence is passed through to the argument as is, without making
624 any special interpretation of the characters in the backslash sequence.
625 In particular, backslashed braces are not counted in locating the
626 matching right brace that terminates the argument.
632 the second argument to `set` will be +{backslash}{abc+.
634 This backslash mechanism is not sufficient to generate absolutely
635 any argument structure; it only covers the
636 most common cases. To produce particularly complicated arguments
637 it is probably easiest to use the `format` command along with
638 command substitution.
640 STRING AND LIST INDEX SPECIFICATIONS
641 ------------------------------------
643 Many string and list commands take one or more 'index' parameters which
644 specify a position in the string relative to the start or end of the string/list.
646 The index may be one of the following forms:
649 A simple integer, where '0' refers to the first element of the string
652 +integer+integer+ or::
654 The sum or difference of the two integers. e.g. +2+3+ refers to the 5th element.
655 This is useful when used with (e.g.) +$i+1+ rather than the more verbose
659 The last element of the string or list.
662 The 'nth-from-last' element of the string or list.
666 1. A command is just a string.
667 2. Within a string commands are separated by newlines or semi-colons
668 (unless the newline or semi-colon is within braces or brackets
670 3. A command consists of fields. The first field is the name of the command.
671 The other fields are strings that are passed to that command as arguments.
672 4. Fields are normally separated by white space.
673 5. Double-quotes allow white space and semi-colons to appear within
675 Command substitution, variable substitution, and backslash substitution
676 still occur inside quotes.
677 6. Braces defer interpretation of special characters.
678 If a field begins with a left brace, then it consists of everything
679 between the left brace and the matching right brace. The
680 braces themselves are not included in the argument.
681 No further processing is done on the information between the braces
682 except that backslash-newline sequences are eliminated.
683 7. If a field doesn't begin with a brace then backslash,
684 variable, and command substitution are done on the field. Only a
685 single level of processing is done: the results of one substitution
686 are not scanned again for further substitutions or any other
687 special treatment. Substitution can
688 occur on any field of a command, including the command name
689 as well as the arguments.
690 8. If the first non-blank character of a command is a +\#+, everything
691 from the +#+ up through the next newline is treated as a comment
696 The second major interpretation applied to strings in Tcl is
697 as expressions. Several commands, such as `expr`, `for`,
698 and `if`, treat one or more of their arguments as expressions
699 and call the Tcl expression processors ('Jim_ExprLong',
700 'Jim_ExprBoolean', etc.) to evaluate them.
702 The operators permitted in Tcl expressions are a subset of
703 the operators permitted in C expressions, and they have the
704 same meaning and precedence as the corresponding C operators.
705 Expressions almost always yield numeric results
706 (integer or floating-point values).
707 For example, the expression
713 Tcl expressions differ from C expressions in the way that
714 operands are specified, and in that Tcl expressions support
715 non-numeric operands and string comparisons.
717 A Tcl expression consists of a combination of operands, operators,
720 White space may be used between the operands and operators and
721 parentheses; it is ignored by the expression processor.
722 Where possible, operands are interpreted as integer values.
724 Integer values may be specified in decimal (the normal case) or in
725 hexadecimal (if the first two characters of the operand are '0x').
726 Note that Jim Tcl does *not* treat numbers with leading zeros as octal.
728 If an operand does not have one of the integer formats given
729 above, then it is treated as a floating-point number if that is
730 possible. Floating-point numbers may be specified in any of the
731 ways accepted by an ANSI-compliant C compiler (except that the
732 'f', 'F', 'l', and 'L' suffixes will not be permitted in
733 most installations). For example, all of the
734 following are valid floating-point numbers: 2.1, 3., 6e4, 7.91e+16.
736 If no numeric interpretation is possible, then an operand is left
737 as a string (and only a limited set of operators may be applied to
740 String constants representing boolean constants
741 (+'0'+, +'1'+, +'false'+, +'off'+, +'no'+, +'true'+, +'on'+, +'yes'+)
742 are also recognized and can be used in logical operations.
744 1. Operands may be specified in any of the following ways:
746 2. As a numeric value, either integer or floating-point.
748 3. As one of valid boolean constants
750 4. As a Tcl variable, using standard '$' notation.
751 The variable's value will be used as the operand.
753 5. As a string enclosed in double-quotes.
754 The expression parser will perform backslash, variable, and
755 command substitutions on the information between the quotes,
756 and use the resulting value as the operand
758 6. As a string enclosed in braces.
759 The characters between the open brace and matching close brace
760 will be used as the operand without any substitutions.
762 7. As a Tcl command enclosed in brackets.
763 The command will be executed and its result will be used as
766 Where substitutions occur above (e.g. inside quoted strings), they
767 are performed by the expression processor.
768 However, an additional layer of substitution may already have
769 been performed by the command parser before the expression
770 processor was called.
772 As discussed below, it is usually best to enclose expressions
773 in braces to prevent the command parser from performing substitutions
776 For some examples of simple expressions, suppose the variable 'a' has
777 the value 3 and the variable 'b' has the value 6. Then the expression
778 on the left side of each of the lines below will evaluate to the value
779 on the right side of the line:
784 {word one} < "word $a" 0
786 The valid operators are listed below, grouped in decreasing order
788 [[OperatorPrecedence]]
789 +int() double() round() abs(), rand(), srand()+::
790 Unary functions (except rand() which takes no arguments)
791 * +'int()'+ converts the numeric argument to an integer by truncating down.
792 * +'double()'+ converts the numeric argument to floating point.
793 * +'round()'+ converts the numeric argument to the closest integer value.
794 * +'abs()'+ takes the absolute value of the numeric argument.
795 * +'rand()'+ returns a pseudo-random floating-point value in the range (0,1).
796 * +'srand()'+ takes an integer argument to (re)seed the random number generator. Returns the first random number from that seed.
798 +sin() cos() tan() asin() acos() atan() sinh() cosh() tanh() ceil() floor() exp() log() log10() sqrt()+::
799 Unary math functions.
800 If Jim is compiled with math support, these functions are available.
803 Unary minus, unary plus, bit-wise NOT, logical NOT. None of these operands
804 may be applied to string operands, and bit-wise NOT may be
805 applied only to integers.
808 Power. e.g. 'x^y^'. If Jim is compiled with math support, supports doubles and
809 integers. Otherwise supports integers only. (Note that the math-function form
810 has the same highest precedence)
813 Multiply, divide, remainder. None of these operands may be
814 applied to string operands, and remainder may be applied only
818 Add and subtract. Valid for any numeric operands.
821 Left and right shift, left and right rotate. Valid for integer operands only.
824 Boolean less, greater, less than or equal, and greater than or equal.
825 Each operator produces 1 if the condition is true, 0 otherwise.
826 These operators may be applied to strings as well as numeric operands,
827 in which case string comparison is used.
830 Boolean equal and not equal. Each operator produces a zero/one result.
831 Valid for all operand types. *Note* that values will be converted to integers
832 if possible, then floating point types, and finally strings will be compared.
833 It is recommended that 'eq' and 'ne' should be used for string comparison.
836 String equal and not equal. Uses the string value directly without
837 attempting to convert to a number first.
840 String in list and not in list. For 'in', result is 1 if the left operand (as a string)
841 is contained in the right operand (as a list), or 0 otherwise. The result for
842 +{$a ni $list}+ is equivalent to +{!($a in $list)}+.
845 Bit-wise AND. Valid for integer operands only.
848 Bit-wise OR. Valid for integer operands only.
851 Bit-wise exclusive OR. Valid for integer operands only.
854 Logical AND. Produces a 1 result if both operands are non-zero, 0 otherwise.
855 Valid for numeric operands only (integers or floating-point).
858 Logical OR. Produces a 0 result if both operands are zero, 1 otherwise.
859 Valid for numeric operands only (integers or floating-point).
862 If-then-else, as in C. If +'x'+
863 evaluates to non-zero, then the result is the value of +'y'+.
864 Otherwise the result is the value of +'z'+.
865 The +'x'+ operand must have a numeric value, while +'y'+ and +'z'+ can
868 See the C manual for more details on the results
869 produced by each operator.
870 All of the binary operators group left-to-right within the same
871 precedence level. For example, the expression
877 The +&&+, +||+, and +?:+ operators have 'lazy evaluation', just as
878 in C, which means that operands are not evaluated if they are not
879 needed to determine the outcome. For example, in
883 only one of +[a]+ or +[b]+ will actually be evaluated,
884 depending on the value of +$v+.
886 All internal computations involving integers are done with the C
887 type 'long long' if available, or 'long' otherwise, and all internal
888 computations involving floating-point are done with the C type
891 When converting a string to floating-point, exponent overflow is
892 detected and results in a Tcl error.
893 For conversion to integer from string, detection of overflow depends
894 on the behaviour of some routines in the local C library, so it should
895 be regarded as unreliable.
896 In any case, overflow and underflow are generally not detected
897 reliably for intermediate results.
899 Conversion among internal representations for integer, floating-point,
900 string operands is done automatically as needed.
901 For arithmetic computations, integers are used until some
902 floating-point number is introduced, after which floating-point is used.
907 yields the result 1, while
910 5 / ( [string length "abcd"] + 0.0 )
912 both yield the result 1.25.
914 String values may be used as operands of the comparison operators,
915 although the expression evaluator tries to do comparisons as integer
916 or floating-point when it can.
917 If one of the operands of a comparison is a string and the other
918 has a numeric value, the numeric operand is converted back to
919 a string using the C 'sprintf' format specifier
920 '%d' for integers and '%g' for floating-point values.
921 For example, the expressions
926 both evaluate to 1. The first comparison is done using integer
927 comparison, and the second is done using string comparison after
928 the second operand is converted to the string '18'.
930 In general it is safest to enclose an expression in braces when
931 entering it in a command: otherwise, if the expression contains
932 any white space then the Tcl interpreter will split it
933 among several arguments. For example, the command
937 results in three arguments being passed to `expr`: +$a+,
938 \+, and +$b+. In addition, if the expression isn't in braces
939 then the Tcl interpreter will perform variable and command substitution
940 immediately (it will happen in the command parser rather than in
941 the expression parser). In many cases the expression is being
942 passed to a command that will evaluate the expression later (or
943 even many times if, for example, the expression is to be used to
944 decide when to exit a loop). Usually the desired goal is to re-do
945 the variable or command substitutions each time the expression is
946 evaluated, rather than once and for all at the beginning. For example,
949 for {set i 1} $i<=10 {incr i} {...} ** WRONG **
951 is probably intended to iterate over all values of +i+ from 1 to 10.
952 After each iteration of the body of the loop, `for` will pass
953 its second argument to the expression evaluator to see whether or not
954 to continue processing. Unfortunately, in this case the value of +i+
955 in the second argument will be substituted once and for all when the
956 `for` command is parsed. If +i+ was 0 before the `for`
957 command was invoked then the second argument of `for` will be +0\<=10+
958 which will always evaluate to 1, even though +i+ eventually
959 becomes greater than 10. In the above case the loop will never
960 terminate. Instead, the expression should be placed in braces:
962 for {set i 1} {$i<=10} {incr i} {...} ** RIGHT **
964 This causes the substitution of 'i'
965 to be delayed; it will be re-done each time the expression is
966 evaluated, which is the desired result.
970 The third major way that strings are interpreted in Tcl is as lists.
971 A list is just a string with a list-like structure
972 consisting of fields separated by white space. For example, the
977 is a list with four elements or fields.
978 Lists have the same basic structure as command strings, except
979 that a newline character in a list is treated as a field separator
980 just like space or tab. Conventions for braces and quotes
981 and backslashes are the same for lists as for commands. For example,
986 is a list with three elements: +a+, +b c+, and +d e {f g h}+.
988 Whenever an element is extracted from a list, the same rules about
989 braces and quotes and backslashes are applied as for commands. Thus in
990 the example above when the third element is extracted from the list,
995 (when the field was extracted, all that happened was to strip off
996 the outermost layer of braces). Command substitution and
997 variable substitution are never
998 made on a list (at least, not by the list-processing commands; the
999 list can always be passed to the Tcl interpreter for evaluation).
1001 The Tcl commands `concat`, `foreach`, `lappend`, `lindex`, `linsert`,
1002 `list`, `llength`, `lrange`, `lreplace`, `lsearch`, and `lsort` allow
1003 you to build lists, extract elements from them, search them, and perform
1004 other list-related functions.
1006 Advanced list commands include `lrepeat`, `lreverse`, `lmap`, `lassign`, `lset`.
1011 A new addition to Tcl 8.5 is the ability to expand a list into separate
1012 arguments. Support for this feature is also available in Jim.
1014 Consider the following attempt to exec a list:
1019 This will attempt to exec a command named "ls -l", which will clearly not
1020 work. Typically eval and concat are required to solve this problem, however
1021 it can be solved much more easily with +\{*\}+.
1025 This will expand the following argument into individual elements and then evaluate
1026 the resulting command.
1028 Note that the official Tcl syntax is +\{*\}+, however +\{expand\}+ is retained
1029 for backward compatibility with experimental versions of this feature.
1033 Tcl provides two commands that support string matching using regular
1034 expressions, `regexp` and `regsub`, as well as `switch -regexp` and
1037 Regular expressions may be implemented one of two ways. Either using the system's C library
1038 POSIX regular expression support, or using the built-in regular expression engine.
1039 The differences between these are described below.
1041 *NOTE* Tcl 7.x and 8.x use perl-style Advanced Regular Expressions (+ARE+).
1043 POSIX Regular Expressions
1044 ~~~~~~~~~~~~~~~~~~~~~~~~~
1045 If the system supports POSIX regular expressions, and UTF-8 support is not enabled,
1046 this support will be used by default. The type of regular expressions supported are
1047 Extended Regular Expressions (+ERE+) rather than Basic Regular Expressions (+BRE+).
1048 See REG_EXTENDED in the documentation.
1050 Using the system-supported POSIX regular expressions will typically
1051 make for the smallest code size, but some features such as UTF-8
1052 and +{backslash}w+, +{backslash}d+, +{backslash}s+ are not supported, and null characters
1053 in strings are not supported.
1055 See regex(3) and regex(7) for full details.
1057 Jim built-in Regular Expressions
1058 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1059 The Jim built-in regular expression engine may be selected with +./configure --with-jim-regexp+
1060 or it will be selected automatically if UTF-8 support is enabled.
1062 This engine supports UTF-8 as well as some +ARE+ features. The differences with both Tcl 7.x/8.x
1063 and POSIX are highlighted below.
1065 1. UTF-8 strings and patterns are both supported
1066 2. All Tcl character classes are supported (e.g. +[:alnum:]+, +[:digit:]+, +[:space:]+), but...
1067 3. Character classes apply to ASCII characters only
1068 4. Supported shorthand character classes: +{backslash}w+ = +[:alnum:]+, +{backslash}W+ = +^[:alnum:]+, +{backslash}d+ = +[:digit:],+ +{backslash}D+ = +^[:digit:],+ +{backslash}s+ = +[:space:]+, + +{backslash}S+ = +^[:space:]+
1069 5. Supported constraint escapes: +{backslash}m+ = +{backslash}<+ = start of word, +{backslash}M+ = +{backslash}>+ = end of word
1070 6. Backslash escapes may be used within regular expressions, such as +{backslash}n+ = newline, +{backslash}uNNNN+ = unicode
1071 7. Partially supported constraint escapes: +{backslash}A+ = start of string, +{backslash}Z+ = end of string
1072 8. Support for the +?+ non-greedy quantifier. e.g. +*?+
1073 9. Support for non-capturing parentheses +(?:...)+
1074 10. Jim Tcl considers that both patterns and strings end at a null character (+\x00+)
1078 Each command produces two results: a code and a string. The
1079 code indicates whether the command completed successfully or not,
1080 and the string gives additional information. The valid codes are
1081 defined in jim.h, and are:
1084 This is the normal return code, and indicates that the command completed
1085 successfully. The string gives the command's return value.
1088 Indicates that an error occurred; the string gives a message describing
1092 Indicates that the `return` command has been invoked, and that the
1093 current procedure (or top-level command or `source` command)
1094 should return immediately. The
1095 string gives the return value for the procedure or command.
1098 Indicates that the `break` command has been invoked, so the
1099 innermost loop should abort immediately. The string should always
1103 Indicates that the `continue` command has been invoked, so the
1104 innermost loop should go on to the next iteration. The string
1105 should always be empty.
1108 Indicates that a signal was caught while executing a commands.
1109 The string contains the name of the signal caught.
1110 See the `signal` and `catch` commands.
1113 Indicates that the command called the `exit` command.
1114 The string contains the exit code.
1116 Tcl programmers do not normally need to think about return codes,
1117 since +JIM_OK+ is almost always returned. If anything else is returned
1118 by a command, then the Tcl interpreter immediately stops processing
1119 commands and returns to its caller. If there are several nested
1120 invocations of the Tcl interpreter in progress, then each nested
1121 command will usually return the error to its caller, until eventually
1122 the error is reported to the top-level application code. The
1123 application will then display the error message for the user.
1125 In a few cases, some commands will handle certain `error` conditions
1126 themselves and not return them upwards. For example, the `for`
1127 command checks for the +JIM_BREAK+ code; if it occurs, then `for`
1128 stops executing the body of the loop and returns +JIM_OK+ to its
1129 caller. The `for` command also handles +JIM_CONTINUE+ codes and the
1130 procedure interpreter handles +JIM_RETURN+ codes. The `catch`
1131 command allows Tcl programs to catch errors and handle them without
1132 aborting command interpretation any further.
1134 The `info returncodes` command may be used to programmatically map between
1135 return codes and names.
1139 Tcl allows you to extend the command interface by defining
1140 procedures. A Tcl procedure can be invoked just like any other Tcl
1141 command (it has a name and it receives one or more arguments).
1142 The only difference is that its body isn't a piece of C code linked
1143 into the program; it is a string containing one or more other
1146 The `proc` command is used to create a new Tcl command procedure:
1148 +*proc* 'name arglist ?statics? body'+
1150 The new command is named +'name'+, and it replaces any existing command
1151 there may have been by that name. Whenever the new command is
1152 invoked, the contents of +'body'+ will be executed by the Tcl
1155 +'arglist'+ specifies the formal arguments to the procedure.
1156 It consists of a list, possibly empty, of the following
1157 argument specifiers:
1160 Required Argument - A simple argument name.
1163 Optional Argument - A two-element list consisting of the
1164 argument name, followed by the default value, which will
1165 be used if the corresponding argument is not supplied.
1168 Reference Argument - The caller is expected to pass the name of
1169 an existing variable. An implicit +`upvar` 1 origname name+ is done
1170 to make the variable available in the proc scope.
1173 Variable Argument - The special name +'args'+, which is
1174 assigned all remaining arguments (including none) as a list. The
1175 variable argument may only be specified once. Note that
1176 the syntax +{args newname}+ may be used to retain the special
1177 behaviour of +'args'+ with a different local name. In this case,
1178 the variable is named +'newname'+ rather than +'args'+.
1180 When the command is invoked, a local variable will be created for each of
1181 the formal arguments to the procedure; its value will be the value
1182 of corresponding argument in the invoking command or the argument's
1185 Arguments with default values need not be specified in a procedure
1186 invocation. However, there must be enough actual arguments for all
1187 required arguments, and there must not be any extra actual arguments
1188 (unless the Variable Argument is specified).
1190 Actual arguments are assigned to formal arguments as in left-to-right
1191 order with the following precedence.
1193 1. Required Arguments (including Reference Arguments)
1194 2. Optional Arguments
1195 3. Variable Argument
1197 The following example illustrates precedence. Assume a procedure declaration:
1199 proc p {{a A} args b {c C} d} {...}
1201 This procedure requires at least two arguments, but can accept an unlimited number.
1202 The following table shows how various numbers of arguments are assigned.
1203 Values marked as +-+ are assigned the default value.
1205 [width="40%",frame="topbot",options="header"]
1207 |Number of arguments|a|args|b|c|d
1215 When +'body'+ is being executed, variable names normally refer to local
1216 variables, which are created automatically when referenced and deleted
1217 when the procedure returns. One local variable is automatically created
1218 for each of the procedure's arguments. Global variables can be
1219 accessed by invoking the `global` command or via the +::+ prefix.
1223 In addition to procedure arguments, Jim procedures may declare static variables.
1224 These variables scoped to the procedure and initialised at procedure definition.
1225 Either from the static variable definition, or from the enclosing scope.
1227 Consider the following example:
1230 jim> proc a {} {a {b 2}} {
1242 The static variable +'a'+ has no initialiser, so it is initialised from
1243 the enclosing scope with the value 1. (Note that it is an error if there
1244 is no variable with the same name in the enclosing scope). However +'b'+
1245 has an initialiser, so it is initialised to 2.
1247 Unlike a local variable, the value of a static variable is retained across
1248 invocations of the procedure.
1250 See the `proc` command for information on how to define procedures
1251 and what happens when they are invoked. See also NAMESPACES.
1253 VARIABLES - SCALARS AND ARRAYS
1254 ------------------------------
1255 Tcl allows the definition of variables and the use of their values
1256 either through '$'-style variable substitution, the `set`
1257 command, or a few other mechanisms.
1259 Variables need not be declared: a new variable will automatically
1260 be created each time a new variable name is used.
1262 Tcl supports two types of variables: scalars and arrays.
1263 A scalar variable has a single value, whereas an array variable
1264 can have any number of elements, each with a name (called
1265 its 'index') and a value.
1267 Array indexes may be arbitrary strings; they need not be numeric.
1268 Parentheses are used refer to array elements in Tcl commands.
1269 For example, the command
1273 will modify the element of 'x' whose index is 'first'
1274 so that its new value is '44'.
1276 Two-dimensional arrays can be simulated in Tcl by using indexes
1277 that contain multiple concatenated values.
1278 For example, the commands
1283 set the elements of 'a' whose indexes are '2,3' and '3,6'.
1285 In general, array elements may be used anywhere in Tcl that scalar
1286 variables may be used.
1288 If an array is defined with a particular name, then there may
1289 not be a scalar variable with the same name.
1291 Similarly, if there is a scalar variable with a particular
1292 name then it is not possible to make array references to the
1295 To convert a scalar variable to an array or vice versa, remove
1296 the existing variable with the `unset` command.
1298 The `array` command provides several features for dealing
1299 with arrays, such as querying the names of all the elements of
1300 the array and converting between an array and a list.
1302 Variables may be either global or local. If a variable
1303 name is used when a procedure isn't being executed, then it
1304 automatically refers to a global variable. Variable names used
1305 within a procedure normally refer to local variables associated with that
1306 invocation of the procedure. Local variables are deleted whenever
1307 a procedure exits. Either `global` command may be used to request
1308 that a name refer to a global variable for the duration of the current
1309 procedure (this is somewhat analogous to 'extern' in C), or the variable
1310 may be explicitly scoped with the +::+ prefix. For example
1326 ARRAYS AS LISTS IN JIM
1327 ----------------------
1328 Unlike Tcl, Jim can automatically convert between a list (with an even
1329 number of elements) and an array value. This is similar to the way Tcl
1330 can convert between a string and a list.
1341 Thus `array set` is equivalent to `set` when the variable does not
1344 The reverse is also true where an array will be converted into
1347 set a(1) one; set a(2) two
1356 Tcl 8.5 introduced the dict command, and Jim Tcl has added a version
1357 of this command. Dictionaries provide efficient access to key-value
1358 pairs, just like arrays, but dictionaries are pure values. This
1359 means that you can pass them to a procedure just as a list or a
1360 string. Tcl dictionaries are therefore much more like Tcl lists,
1361 except that they represent a mapping from keys to values, rather
1362 than an ordered sequence.
1364 You can nest dictionaries, so that the value for a particular key
1365 consists of another dictionary. That way you can elegantly build
1366 complicated data structures, such as hierarchical databases. You
1367 can also combine dictionaries with other Tcl data structures. For
1368 instance, you can build a list of dictionaries that themselves
1371 Dictionaries are values that contain an efficient, order-preserving
1372 mapping from arbitrary keys to arbitrary values. Each key in the
1373 dictionary maps to a single value. They have a textual format that
1374 is exactly that of any list with an even number of elements, with
1375 each mapping in the dictionary being represented as two items in
1376 the list. When a command takes a dictionary and produces a new
1377 dictionary based on it (either returning it or writing it back into
1378 the variable that the starting dictionary was read from) the new
1379 dictionary will have the same order of keys, modulo any deleted
1380 keys and with new keys added on to the end. When a string is
1381 interpreted as a dictionary and it would otherwise have duplicate
1382 keys, only the last value for a particular key is used; the others
1383 are ignored, meaning that, "apple banana" and "apple carrot apple
1384 banana" are equivalent dictionaries (with different string
1387 Note that in Jim, arrays are implemented as dictionaries.
1388 Thus automatic conversion between lists and dictionaries applies
1389 as it does for arrays.
1391 jim> dict set a 1 one
1393 jim> dict set a 2 two
1399 jim> dict set a 3 T three
1400 1 one 2 two 3 {T three}
1402 See the `dict` command for more details.
1406 Tcl added namespaces as a mechanism avoiding name clashes, especially in applications
1407 including a number of 3rd party components. While there is less need for namespaces
1408 in Jim Tcl (which does not strive to support large applications), it is convenient to
1409 provide a subset of the support for namespaces to easy porting code from Tcl.
1411 Jim Tcl currently supports "light-weight" namespaces which should be adequate for most
1412 purposes. This feature is currently experimental. See README.namespaces for more information
1413 and the documentation of the `namespace` command.
1415 GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION
1416 -----------------------------------------------
1417 Unlike Tcl, Jim has some sophisticated support for functional programming.
1418 These are described briefly below.
1420 More information may be found at http://wiki.tcl.tk/13847
1424 A reference can be thought of as holding a value with one level of indirection,
1425 where the value may be garbage collected when unreferenced.
1426 Consider the following example:
1428 jim> set r [ref "One String" test]
1429 <reference.<test___>.00000000000000000000>
1433 The operation `ref` creates a references to the value specified by the
1434 first argument. (The second argument is a "type" used for documentation purposes).
1436 The operation `getref` is the dereferencing operation which retrieves the value
1437 stored in the reference.
1439 jim> setref $r "New String"
1444 The operation `setref` replaces the value stored by the reference. If the old value
1445 is no longer accessible by any reference, it will eventually be automatically be garbage
1450 Normally, all values in Tcl are passed by value. As such values are copied and released
1451 automatically as necessary.
1453 With the introduction of references, it is possible to create values whose lifetime
1454 transcend their scope. To support this, case, the Jim system will periodically identify
1455 and discard objects which are no longer accessible by any reference.
1457 The `collect` command may be used to force garbage collection. Consider a reference created
1460 jim> proc f {ref value} { puts "Finaliser called for $ref,$value" }
1461 jim> set r [ref "One String" test f]
1462 <reference.<test___>.00000000000
1467 Finaliser called for <reference.<test___>.00000000000,One String
1470 Note that once the reference, 'r', was modified so that it no longer
1471 contained a reference to the value, the garbage collector discarded
1472 the value (after calling the finalizer).
1474 The finalizer for a reference may be examined or changed with the `finalize` command
1478 jim> finalize $r newf
1483 Jim provides a garbage collected `lambda` function. This is a procedure
1484 which is able to create an anonymous procedure. Consider:
1486 jim> set f [lambda {a} {{x 0}} { incr x $a }]
1493 This create an anonymous procedure (with the name stored in 'f'), with a static variable
1494 which is incremented by the supplied value and the result returned.
1496 Once the procedure name is no longer accessible, it will automatically be deleted
1497 when the garbage collector runs.
1499 The procedure may also be delete immediately by renaming it "". e.g.
1505 If Jim is built with UTF-8 support enabled (configure --enable-utf),
1506 then most string-related commands become UTF-8 aware. These include,
1507 but are not limited to, `string match`, `split`, `glob`, `scan` and
1510 UTF-8 encoding has many advantages, but one of the complications is that
1511 characters can take a variable number of bytes. Thus the addition of
1512 `string bytelength` which returns the number of bytes in a string,
1513 while `string length` returns the number of characters.
1515 If UTF-8 support is not enabled, all commands treat bytes as characters
1516 and `string bytelength` returns the same value as `string length`.
1518 Note that even if UTF-8 support is not enabled, the +{backslash}uNNNN+ and related syntax
1519 is still available to embed UTF-8 sequences.
1521 Jim Tcl supports all currently defined unicode codepoints. That is 21 bits, up to +'U+1FFFFF'.
1525 Commands such as `string match`, `lsearch -glob`, `array names` and others use string
1526 pattern matching rules. These commands support UTF-8. For example:
1528 string match a\[\ua0-\ubf\]b "a\u00a3b"
1532 +format %c+ allows a unicode codepoint to be be encoded. For example, the following will return
1533 a string with two bytes and one character. The same as +{backslash}ub5+
1537 `format` respects widths as character widths, not byte widths. For example, the following will
1538 return a string with three characters, not three bytes.
1540 format %.3s \ub5\ub6\ub7\ub8
1542 Similarly, +scan ... %c+ allows a UTF-8 to be decoded to a unicode codepoint. The following will set
1543 +'a'+ to 181 (0xb5) and +'b'+ to 65 (0x41).
1545 scan \u00b5A %c%c a b
1547 `scan %s` will also accept a character class, including unicode ranges.
1551 `string is` has *not* been extended to classify UTF-8 characters. Therefore, the following
1552 will return 0, even though the string may be considered to be alphabetic.
1554 string is alpha \ub5Test
1556 This does not affect the string classes 'ascii', 'control', 'digit', 'double', 'integer' or 'xdigit'.
1558 Case Mapping and Conversion
1559 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
1560 Jim provides a simplified unicode case mapping. This means that case conversion
1561 and comparison will not increase or decrease the number of characters in a string.
1562 (Although it may change the number of bytes).
1564 `string toupper` will convert any lowercase letters to their uppercase equivalent.
1565 Any character which is not a letter or has no uppercase equivalent is left unchanged.
1566 Similarly for `string tolower` and `string totitle`.
1568 Commands which perform case insensitive matches, such as `string compare -nocase`
1569 and `lsearch -nocase` fold both strings to uppercase before comparison.
1571 Invalid UTF-8 Sequences
1572 ~~~~~~~~~~~~~~~~~~~~~~~
1573 Some UTF-8 character sequences are invalid, such as those beginning with '0xff',
1574 those which represent character sequences longer than 3 bytes (greater than U+FFFF),
1575 and those which end prematurely, such as a lone '0xc2'.
1577 In these situations, the offending bytes are treated as single characters. For example,
1578 the following returns 2.
1580 string bytelength \xff\xff
1584 If UTF-8 support is enabled, the built-in regular expression engine will be
1585 selected which supports UTF-8 strings and patterns.
1587 See REGULAR EXPRESSIONS
1591 The Tcl library provides the following built-in commands, which will
1592 be available in any application using Tcl. In addition to these
1593 built-in commands, there may be additional commands defined by each
1594 application, plus commands defined as Tcl procedures.
1596 In the command syntax descriptions below, words in +*boldface*+ are
1597 literals that you type verbatim to Tcl.
1599 Words in +'italics'+ are meta-symbols; they serve as names for any of
1600 a range of values that you can type.
1602 Optional arguments or groups of arguments are indicated by enclosing them
1603 in +?question-marks?+.
1605 Ellipses (+\...+) indicate that any number of additional
1606 arguments or groups of arguments may appear, in the same format
1607 as the preceding argument(s).
1618 Delivers the +SIGALRM+ signal to the process after the given
1619 number of seconds. If the platform supports 'ualarm(3)' then
1620 the argument may be a floating point value. Otherwise it must
1623 Note that unless a signal handler for +SIGALRM+ has been installed
1624 (see `signal`), the process will exit on this signal.
1628 +*alias* 'name args\...'+
1630 Creates a single word alias (command) for one or more words. For example,
1631 the following creates an alias for the command `info exists`.
1638 `alias` returns +'name'+, allowing it to be used with `local`.
1640 See also `proc`, `curry`, `lambda`, `local`, `info alias`, `exists -alias`
1644 +*append* 'varName value ?value value ...?'+
1646 Append all of the +'value'+ arguments to the current value
1647 of variable +'varName'+. If +'varName'+ doesn't exist,
1648 it is given a value equal to the concatenation of all the
1649 +'value'+ arguments.
1651 This command provides an efficient way to build up long
1652 variables incrementally.
1653 For example, "`append a $b`" is much more efficient than
1654 "`set a $a$b`" if +$a+ is long.
1658 +*apply* 'lambdaExpr ?arg1 arg2 \...?'+
1660 The command `apply` provides for anonymous procedure calls,
1661 similar to `lambda`, but without command name being created, even temporarily.
1663 The function +'lambdaExpr'+ is a two element list +{args body}+
1664 or a three element list +{args body namespace}+. The first element
1665 args specifies the formal arguments, in the same form as the `proc` and `lambda` commands.
1669 +*array* 'option arrayName ?arg\...?'+
1671 This command performs one of several operations on the
1672 variable given by +'arrayName'+.
1674 Note that in general, if the named array does not exist, the +'array'+ command behaves
1675 as though the array exists but is empty.
1677 The +'option'+ argument determines what action is carried out by the
1678 command. The legal +'options'+ (which may be abbreviated) are:
1680 +*array exists* 'arrayName'+::
1681 Returns 1 if arrayName is an array variable, 0 if there is
1682 no variable by that name.
1684 +*array get* 'arrayName ?pattern?'+::
1685 Returns a list containing pairs of elements. The first
1686 element in each pair is the name of an element in arrayName
1687 and the second element of each pair is the value of the
1688 array element. The order of the pairs is undefined. If
1689 pattern is not specified, then all of the elements of the
1690 array are included in the result. If pattern is specified,
1691 then only those elements whose names match pattern (using
1692 the matching rules of string match) are included. If arrayName
1693 isn't the name of an array variable, or if the array contains
1694 no elements, then an empty list is returned.
1696 +*array names* 'arrayName ?pattern?'+::
1697 Returns a list containing the names of all of the elements
1698 in the array that match pattern. If pattern is omitted then
1699 the command returns all of the element names in the array.
1700 If pattern is specified, then only those elements whose
1701 names match pattern (using the matching rules of string
1702 match) are included. If there are no (matching) elements
1703 in the array, or if arrayName isn't the name of an array
1704 variable, then an empty string is returned.
1706 +*array set* 'arrayName list'+::
1707 Sets the values of one or more elements in arrayName. list
1708 must have a form like that returned by array get, consisting
1709 of an even number of elements. Each odd-numbered element
1710 in list is treated as an element name within arrayName, and
1711 the following element in list is used as a new value for
1712 that array element. If the variable arrayName does not
1713 already exist and list is empty, arrayName is created with
1714 an empty array value.
1716 +*array size* 'arrayName'+::
1717 Returns the number of elements in the array. If arrayName
1718 isn't the name of an array then 0 is returned.
1720 +*array unset* 'arrayName ?pattern?'+::
1721 Unsets all of the elements in the array that match pattern
1722 (using the matching rules of string match). If arrayName
1723 isn't the name of an array variable or there are no matching
1724 elements in the array, no error will be raised. If pattern
1725 is omitted and arrayName is an array variable, then the
1726 command unsets the entire array. The command always returns
1733 This command may be invoked only inside the body of a loop command
1734 such as `for` or `foreach` or `while`. It returns a +JIM_BREAK+ code
1735 to signal the innermost containing loop command to return immediately.
1739 +*case* 'string' ?in? 'patList body ?patList body ...?'+
1741 +*case* 'string' ?in? {'patList body ?patList body ...?'}+
1743 *Note* that the `switch` command should generally be preferred unless compatibility
1744 with Tcl 6.x is desired.
1746 Match +'string'+ against each of the +'patList'+ arguments
1747 in order. If one matches, then evaluate the following +'body'+ argument
1748 by passing it recursively to the Tcl interpreter, and return the result
1749 of that evaluation. Each +'patList'+ argument consists of a single
1750 pattern or list of patterns. Each pattern may contain any of the wild-cards
1751 described under `string match`.
1753 If a +'patList'+ argument is +default+, the corresponding body will be
1754 evaluated if no +'patList'+ matches +'string'+. If no +'patList'+ argument
1755 matches +'string'+ and no default is given, then the `case` command returns
1758 Two syntaxes are provided.
1760 The first uses a separate argument for each of the patterns and commands;
1761 this form is convenient if substitutions are desired on some of the
1762 patterns or commands.
1764 The second form places all of the patterns and commands together into
1765 a single argument; the argument must have proper list structure, with
1766 the elements of the list being the patterns and commands.
1768 The second form makes it easy to construct multi-line case commands,
1769 since the braces around the whole list make it unnecessary to include a
1770 backslash at the end of each line.
1772 Since the +'patList'+ arguments are in braces in the second form,
1773 no command or variable substitutions are performed on them; this makes
1774 the behaviour of the second form different than the first form in some
1777 Below are some examples of `case` commands:
1779 case abc in {a b} {format 1} default {format 2} a* {format 3}
1789 will return '1', and
1804 +*catch* ?-?no?'code \...'? ?--? 'command ?resultVarName? ?optionsVarName?'+
1806 The `catch` command may be used to prevent errors from aborting
1807 command interpretation. `catch` evaluates +'command'+, and returns a
1808 +JIM_OK+ code, regardless of any errors that might occur while
1809 executing +'command'+ (with the possible exception of +JIM_SIGNAL+ -
1812 The return value from `catch` is a decimal string giving the code
1813 returned by the Tcl interpreter after executing +'command'+. This
1814 will be '0' (+JIM_OK+) if there were no errors in +'command'+; otherwise
1815 it will have a non-zero value corresponding to one of the exceptional
1816 return codes (see jim.h for the definitions of code values, or the
1817 `info returncodes` command).
1819 If the +'resultVarName'+ argument is given, then it gives the name
1820 of a variable; `catch` will set the value of the variable to the
1821 string returned from +'command'+ (either a result or an error message).
1823 If the +'optionsVarName'+ argument is given, then it gives the name
1824 of a variable; `catch` will set the value of the variable to a
1825 dictionary. For any return code other than +JIM_RETURN+, the value
1826 for the key +-code+ will be set to the return code. For +JIM_RETURN+
1827 it will be set to the code given in `return -code`. Additionally,
1828 for the return code +JIM_ERR+, the value of the key +-errorinfo+
1829 will contain the current stack trace (the same result as `info stacktrace`),
1830 the value of the key +-errorcode+ will contain the
1831 same value as the global variable $::errorCode, and the value of
1832 the key +-level+ will be the current return level (see `return -level`).
1833 This can be useful to rethrow an error:
1835 if {[catch {...} msg opts]} {
1836 ...maybe do something with the error...
1838 return {*}$opts $msg
1841 Normally `catch` will +'not'+ catch any of the codes +JIM_EXIT+, +JIM_EVAL+ or +JIM_SIGNAL+.
1842 The set of codes which will be caught may be modified by specifying the one more codes before
1845 e.g. To catch +JIM_EXIT+ but not +JIM_BREAK+ or +JIM_CONTINUE+
1847 catch -exit -nobreak -nocontinue -- { ... }
1849 The use of +--+ is optional. It signifies that no more return code options follow.
1851 Note that if a signal marked as `signal handle` is caught with `catch -signal`, the return value
1852 (stored in +'resultVarName'+) is name of the signal caught.
1858 Change the current working directory to +'dirName'+.
1860 Returns an empty string.
1862 This command can potentially be disruptive to an application, so it may
1863 be removed in some applications.
1868 Returns the current time as seconds since the epoch.
1871 Returns the current time in "clicks", a system-dependent, high-resolution time.
1873 +*clock microseconds*+::
1874 Returns the current time in microseconds.
1876 +*clock milliseconds*+::
1877 Returns the current time in milliseconds.
1879 +*clock format* 'seconds' ?*-format* 'format?' ?*-gmt* 'boolean?'+::
1880 Format the given time (seconds since the epoch) according to the given
1881 format. See strftime(3) for supported formats.
1882 If no format is supplied, "%c" is used.
1884 If +'boolean'+ is true, processing is performed in UTC.
1885 If +'boolean'+ is false (the default), processing is performeed in the local time zone.
1887 +*clock scan* 'str' *-format* 'format' ?*-gmt* 'boolean?'+::
1888 Scan the given time string using the given format string.
1889 See strptime(3) for supported formats.
1890 See `clock format` for the handling of '-gmt'.
1898 Closes the file given by +'fileId'+.
1899 +'fileId'+ must be the return value from a previous invocation
1900 of the `open` command; after this command, it should not be
1907 Normally reference garbage collection is automatically performed periodically.
1908 However it may be run immediately with the `collect` command.
1910 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
1914 +*concat* 'arg ?arg \...?'+
1916 This command treats each argument as a list and concatenates them
1917 into a single list. It permits any number of arguments. For example,
1920 concat a b {c d e} {f {g h}}
1932 This command may be invoked only inside the body of a loop command such
1933 as `for` or `foreach` or `while`. It returns a +JIM_CONTINUE+ code to
1934 signal the innermost containing loop command to skip the remainder of
1935 the loop's body but continue with the next iteration of the loop.
1939 +*alias* 'args\...'+
1941 Similar to `alias` except it creates an anonymous procedure (lambda) instead of
1944 the following creates a local, unnamed alias for the command `info exists`.
1946 set e [local curry info exists]
1951 `curry` returns the name of the procedure.
1953 See also `proc`, `alias`, `lambda`, `local`.
1957 +*dict* 'option ?arg\...?'+
1959 Performs one of several operations on dictionary values.
1961 The +'option'+ argument determines what action is carried out by the
1962 command. The legal +'options'+ are:
1964 +*dict create* '?key value \...?'+::
1965 Create and return a new dictionary value that contains each of
1966 the key/value mappings listed as arguments (keys and values
1967 alternating, with each key being followed by its associated
1970 +*dict exists* 'dictionary key ?key \...?'+::
1971 Returns a boolean value indicating whether the given key (or path
1972 of keys through a set of nested dictionaries) exists in the given
1973 dictionary value. This returns a true value exactly when `dict get`
1974 on that path will succeed.
1976 +*dict get* 'dictionary ?key \...?'+::
1977 Given a dictionary value (first argument) and a key (second argument),
1978 this will retrieve the value for that key. Where several keys are
1979 supplied, the behaviour of the command shall be as if the result
1980 of "`dict get $dictVal $key`" was passed as the first argument to
1981 dict get with the remaining arguments as second (and possibly
1982 subsequent) arguments. This facilitates lookups in nested dictionaries.
1983 If no keys are provided, dict would return a list containing pairs
1984 of elements in a manner similar to array get. That is, the first
1985 element of each pair would be the key and the second element would
1986 be the value for that key. It is an error to attempt to retrieve
1987 a value for a key that is not present in the dictionary.
1989 +*dict keys* 'dictionary ?pattern?'+::
1990 Returns a list of the keys in the dictionary.
1991 If pattern is specified, then only those keys whose
1992 names match +'pattern'+ (using the matching rules of string
1993 match) are included.
1995 +*dict merge* ?'dictionary \...'?+::
1996 Return a dictionary that contains the contents of each of the
1997 +'dictionary'+ arguments. Where two (or more) dictionaries
1998 contain a mapping for the same key, the resulting dictionary
1999 maps that key to the value according to the last dictionary on
2000 the command line containing a mapping for that key.
2002 +*dict set* 'dictionaryName key ?key \...? value'+::
2003 This operation takes the +'name'+ of a variable containing a dictionary
2004 value and places an updated dictionary value in that variable
2005 containing a mapping from the given key to the given value. When
2006 multiple keys are present, this operation creates or updates a chain
2007 of nested dictionaries.
2009 +*dict size* 'dictionary'+::
2010 Return the number of key/value mappings in the given dictionary value.
2012 +*dict unset* 'dictionaryName key ?key \...? value'+::
2013 This operation (the companion to `dict set`) takes the name of a
2014 variable containing a dictionary value and places an updated
2015 dictionary value in that variable that does not contain a mapping
2016 for the given key. Where multiple keys are present, this describes
2017 a path through nested dictionaries to the mapping to remove. At
2018 least one key must be specified, but the last key on the key-path
2019 need not exist. All other components on the path must exist.
2021 +*dict with* 'dictionaryName key ?key \...? script'+::
2022 Execute the Tcl script in +'script'+ with the value for each
2023 key in +'dictionaryName'+ mapped to a variable with the same
2024 name. Where one or more keys are given, these indicate a chain
2025 of nested dictionaries, with the innermost dictionary being the
2026 one opened out for the execution of body. Making +'dictionaryName'+
2027 unreadable will make the updates to the dictionary be discarded,
2028 and this also happens if the contents of +'dictionaryName'+ are
2029 adjusted so that the chain of dictionaries no longer exists.
2030 The result of `dict with` is (unless some kind of error occurs)
2031 the result of the evaluation of body.
2033 The variables are mapped in the scope enclosing the `dict with`;
2034 it is recommended that this command only be used in a local
2035 scope (procedure). Because of this, the variables set by
2036 `dict with` will continue to exist after the command finishes (unless
2037 explicitly unset). Note that changes to the contents of +'dictionaryName'+
2038 only happen when +'script'+ terminates.
2040 +*dict for, values, incr, append, lappend, update, info, replace*+ to be documented...
2044 +*env* '?name? ?default?'+
2046 If +'name'+ is supplied, returns the value of +'name'+ from the initial
2047 environment (see getenv(3)). An error is returned if +'name'+ does not
2048 exist in the environment, unless +'default'+ is supplied - in which case
2049 that value is returned instead.
2051 If no arguments are supplied, returns a list of all environment variables
2052 and their values as +{name value \...}+
2054 See also the global variable +::env+
2062 Returns 1 if an end-of-file condition has occurred on +'fileId'+,
2065 +'fileId'+ must have been the return value from a previous call to `open`,
2066 or it may be +stdin+, +stdout+, or +stderr+ to refer to one of the
2067 standard I/O channels.
2071 +*error* 'message ?stacktrace?'+
2073 Returns a +JIM_ERR+ code, which causes command interpretation to be
2074 unwound. +'message'+ is a string that is returned to the application
2075 to indicate what went wrong.
2077 If the +'stacktrace'+ argument is provided and is non-empty,
2078 it is used to initialize the stacktrace.
2080 This feature is most useful in conjunction with the `catch` command:
2081 if a caught error cannot be handled successfully, +'stacktrace'+ can be used
2082 to return a stack trace reflecting the original point of occurrence
2087 error $errMsg [info stacktrace]
2089 See also `errorInfo`, `info stacktrace`, `catch` and `return`
2093 +*errorInfo* 'error ?stacktrace?'+
2095 Returns a human-readable representation of the given error message and stack trace.
2098 if {[catch {...} error]} {
2099 puts stderr [errorInfo $error [info stacktrace]]
2107 +*eval* 'arg ?arg\...?'+
2109 `eval` takes one or more arguments, which together comprise a Tcl
2110 command (or collection of Tcl commands separated by newlines in the
2111 usual way). `eval` concatenates all its arguments in the same
2112 fashion as the `concat` command, passes the concatenated string to the
2113 Tcl interpreter recursively, and returns the result of that
2114 evaluation (or any error generated by it).
2118 +*exec* 'arg ?arg\...?'+
2120 This command treats its arguments as the specification
2121 of one or more UNIX commands to execute as subprocesses.
2122 The commands take the form of a standard shell pipeline;
2123 +|+ arguments separate commands in the
2124 pipeline and cause standard output of the preceding command
2125 to be piped into standard input of the next command (or +|&+ for
2126 both standard output and standard error).
2128 Under normal conditions the result of the `exec` command
2129 consists of the standard output produced by the last command
2130 in the pipeline followed by the standard error output.
2132 If any of the commands writes to its standard error file,
2133 then this will be included in the result after the standard output
2134 of the last command.
2136 Note that unlike Tcl, data written to standard error does not cause
2137 `exec` to return an error.
2139 If any of the commands in the pipeline exit abnormally or
2140 are killed or suspended, then `exec` will return an error.
2141 If no standard error output was produced, or is redirected,
2142 the error message will include the normal result, as above,
2143 followed by error messages describing the abnormal terminations.
2145 If any standard error output was produced, these abnormal termination
2146 messages are suppressed.
2148 If the last character of the result or error message
2149 is a newline then that character is deleted from the result
2150 or error message for consistency with normal
2153 An +'arg'+ may have one of the following special forms:
2156 The standard output of the last command in the pipeline
2157 is redirected to the file. In this situation `exec`
2158 will normally return an empty string.
2161 As above, but append to the file.
2164 The standard output of the last command in the pipeline is
2165 redirected to the given (writable) file descriptor (e.g. stdout,
2166 stderr, or the result of `open`). In this situation `exec`
2167 will normally return an empty string.
2170 The standard error of the last command in the pipeline
2171 is redirected to the file.
2174 As above, but append to the file.
2177 The standard error of the last command in the pipeline is
2178 redirected to the given (writable) file descriptor.
2181 The standard error of the last command in the pipeline is
2182 redirected to the same file descriptor as the standard output.
2185 Both the standard output and standard error of the last command
2186 in the pipeline is redirected to the file.
2189 As above, but append to the file.
2192 The standard input of the first command in the pipeline
2193 is taken from the file.
2196 The standard input of the first command is taken as the
2197 given immediate value.
2200 The standard input of the first command in the pipeline
2201 is taken from the given (readable) file descriptor.
2203 If there is no redirection of standard input, standard error
2204 or standard output, these are connected to the corresponding
2205 input or output of the application.
2207 If the last +'arg'+ is +&+ then the command will be
2208 executed in background.
2209 In this case the standard output from the last command
2210 in the pipeline will
2211 go to the application's standard output unless
2212 redirected in the command, and error output from all
2213 the commands in the pipeline will go to the application's
2214 standard error file. The return value of exec in this case
2215 is a list of process ids (pids) in the pipeline.
2217 Each +'arg'+ becomes one word for a command, except for
2218 +|+, +<+, +<<+, +>+, and +&+ arguments, and the
2219 arguments that follow +<+, +<<+, and +>+.
2221 The first word in each command is taken as the command name;
2222 the directories in the PATH environment variable are searched for
2223 an executable by the given name.
2225 No `glob` expansion or other shell-like substitutions
2226 are performed on the arguments to commands.
2228 If the command fails, the global $::errorCode (and the -errorcode
2229 option in `catch`) will be set to a list, as follows:
2231 +*CHILDKILLED* 'pid sigName msg'+::
2232 This format is used when a child process has been killed
2233 because of a signal. The pid element will be the process's
2234 identifier (in decimal). The sigName element will be the
2235 symbolic name of the signal that caused the process to
2236 terminate; it will be one of the names from the include
2237 file signal.h, such as SIGPIPE. The msg element will be a
2238 short human-readable message describing the signal, such
2239 as "write on pipe with no readers" for SIGPIPE.
2241 +*CHILDSUSP* 'pid sigName msg'+::
2242 This format is used when a child process has been suspended
2243 because of a signal. The pid element will be the process's
2244 identifier, in decimal. The sigName element will be the
2245 symbolic name of the signal that caused the process to
2246 suspend; this will be one of the names from the include
2247 file signal.h, such as SIGTTIN. The msg element will be a
2248 short human-readable message describing the signal, such
2249 as "background tty read" for SIGTTIN.
2251 +*CHILDSTATUS* 'pid code'+::
2252 This format is used when a child process has exited with a
2253 non-zero exit status. The pid element will be the process's
2254 identifier (in decimal) and the code element will be the
2255 exit code returned by the process (also in decimal).
2257 The environment for the executed command is set from $::env (unless
2258 this variable is unset, in which case the original environment is used).
2262 +*exists ?-var|-proc|-command|-alias?* 'name'+
2264 Checks the existence of the given variable, procedure, command
2265 or alias respectively and returns 1 if it exists or 0 if not. This command
2266 provides a more simplified/convenient version of `info exists`,
2267 `info procs` and `info commands`.
2269 If the type is omitted, a type of '-var' is used. The type may be abbreviated.
2273 +*exit* '?returnCode?'+
2275 Terminate the process, returning +'returnCode'+ to the
2276 parent as the exit status.
2278 If +'returnCode'+ isn't specified then it defaults
2281 Note that exit can be caught with `catch`.
2287 Calls the expression processor to evaluate +'arg'+, and returns
2288 the result as a string. See the section EXPRESSIONS above.
2290 Note that Jim supports a shorthand syntax for `expr` as +$(\...)+
2291 The following two are identical.
2293 set x [expr {3 * 2 + 1}]
2298 +*file* 'option name ?arg\...?'+
2300 Operate on a file or a file name. +'name'+ is the name of a file.
2302 +'option'+ indicates what to do with the file name. Any unique
2303 abbreviation for +'option'+ is acceptable. The valid options are:
2305 +*file atime* 'name'+::
2306 Return a decimal string giving the time at which file +'name'+
2307 was last accessed. The time is measured in the standard UNIX
2308 fashion as seconds from a fixed starting time (often January 1, 1970).
2309 If the file doesn't exist or its access time cannot be queried then an
2312 +*file copy ?-force?* 'source target'+::
2313 Copies file +'source'+ to file +'target'+. The source file must exist.
2314 The target file must not exist, unless +-force+ is specified.
2316 +*file delete ?-force? ?--?* 'name\...'+::
2317 Deletes file or directory +'name'+. If the file or directory doesn't exist, nothing happens.
2318 If it can't be deleted, an error is generated. Non-empty directories will not be deleted
2319 unless the +-force+ options is given. In this case no errors will be generated, even
2320 if the file/directory can't be deleted. Use +'--'+ if there is any possibility of
2321 the first name being +'-force'+.
2323 +*file dirname* 'name'+::
2324 Return all of the characters in +'name'+ up to but not including
2325 the last slash character. If there are no slashes in +'name'+
2326 then return +.+ (a single dot). If the last slash in +'name'+ is its first
2327 character, then return +/+.
2329 +*file executable* 'name'+::
2330 Return '1' if file +'name'+ is executable by
2331 the current user, '0' otherwise.
2333 +*file exists* 'name'+::
2334 Return '1' if file +'name'+ exists and the current user has
2335 search privileges for the directories leading to it, '0' otherwise.
2337 +*file extension* 'name'+::
2338 Return all of the characters in +'name'+ after and including the
2339 last dot in +'name'+. If there is no dot in +'name'+ then return
2342 +*file isdirectory* 'name'+::
2343 Return '1' if file +'name'+ is a directory,
2346 +*file isfile* 'name'+::
2347 Return '1' if file +'name'+ is a regular file,
2350 +*file join* 'arg\...'+::
2351 Joins multiple path components. Note that if any components is
2352 an absolute path, the preceding components are ignored.
2353 Thus +"`file` join /tmp /root"+ returns +"/root"+.
2355 +*file link* ?*-hard|-symbolic*? 'newname target'+::
2356 Creates a hard link (default) or symbolic link from +'newname'+ to +'target'+.
2357 Note that the sense of this command is the opposite of `file rename` and `file copy`
2358 and also of `ln`, but this is compatible with Tcl.
2359 An error is returned if +'target'+ doesn't exist or +'newname'+ already exists.
2361 +*file lstat* 'name varName'+::
2362 Same as 'stat' option (see below) except uses the +'lstat'+
2363 kernel call instead of +'stat'+. This means that if +'name'+
2364 refers to a symbolic link the information returned in +'varName'+
2365 is for the link rather than the file it refers to. On systems that
2366 don't support symbolic links this option behaves exactly the same
2367 as the 'stat' option.
2369 +*file mkdir* 'dir1 ?dir2\...?'+::
2370 Creates each directory specified. For each pathname +'dir'+ specified,
2371 this command will create all non-existing parent directories
2372 as well as +'dir'+ itself. If an existing directory is specified,
2373 then no action is taken and no error is returned. Trying to
2374 overwrite an existing file with a directory will result in an
2375 error. Arguments are processed in the order specified, halting
2376 at the first error, if any.
2378 +*file mtime* 'name ?time?'+::
2379 Return a decimal string giving the time at which file +'name'+
2380 was last modified. The time is measured in the standard UNIX
2381 fashion as seconds from a fixed starting time (often January 1, 1970).
2382 If the file doesn't exist or its modified time cannot be queried then an
2383 error is generated. If +'time'+ is given, sets the modification time
2384 of the file to the given value.
2386 +*file mtimeus* 'name ?time_us?'+::
2387 As for `file mtime` except the time value is in microseconds
2388 since the epoch (see also `clock microseconds`).
2389 Note that some platforms and some filesystems don't support high
2390 resolution timestamps for files.
2392 +*file normalize* 'name'+::
2393 Return the normalized path of +'name'+. See 'realpath(3)'.
2395 +*file owned* 'name'+::
2396 Return '1' if file +'name'+ is owned by the current user,
2399 +*file readable* 'name'+::
2400 Return '1' if file +'name'+ is readable by
2401 the current user, '0' otherwise.
2403 +*file readlink* 'name'+::
2404 Returns the value of the symbolic link given by +'name'+ (i.e. the
2405 name of the file it points to). If
2406 +'name'+ isn't a symbolic link or its value cannot be read, then
2407 an error is returned. On systems that don't support symbolic links
2408 this option is undefined.
2410 +*file rename* ?*-force*? 'oldname' 'newname'+::
2411 Renames the file from the old name to the new name.
2412 If +'newname'+ already exists, an error is returned unless +'-force'+ is
2415 +*file rootname* 'name'+::
2416 Return all of the characters in +'name'+ up to but not including
2417 the last '.' character in the name. If +'name'+ doesn't contain
2418 a dot, then return +'name'+.
2420 +*file size* 'name'+::
2421 Return a decimal string giving the size of file +'name'+ in bytes.
2422 If the file doesn't exist or its size cannot be queried then an
2425 +*file stat* 'name ?varName?'+::
2426 Invoke the 'stat' kernel call on +'name'+, and return the result
2427 as a dictionary with the following keys: 'atime',
2428 'ctime', 'dev', 'gid', 'ino', 'mode', 'mtime',
2429 'nlink', 'size', 'type', 'uid', 'mtimeus' (if supported - see `file mtimeus`)
2430 Each element except 'type' is a decimal string with the value of
2431 the corresponding field from the 'stat' return structure; see the
2432 manual entry for 'stat' for details on the meanings of the values.
2433 The 'type' element gives the type of the file in the same form
2434 returned by the command `file type`.
2435 If +'varName'+ is specified, it is taken to be the name of an array
2436 variable and the values are also stored into the array.
2438 +*file tail* 'name'+::
2439 Return all of the characters in +'name'+ after the last slash.
2440 If +'name'+ contains no slashes then return +'name'+.
2442 +*file tempfile* '?template?'+::
2443 Creates and returns the name of a unique temporary file. If +'template'+ is omitted, a
2444 default template will be used to place the file in /tmp. See 'mkstemp(3)' for
2445 the format of the template and security concerns.
2447 +*file type* 'name'+::
2448 Returns a string giving the type of file +'name'+, which will be
2449 one of +file+, +directory+, +characterSpecial+,
2450 +blockSpecial+, +fifo+, +link+, or +socket+.
2452 +*file writable* 'name'+::
2453 Return '1' if file +'name'+ is writable by
2454 the current user, '0' otherwise.
2456 The `file` commands that return 0/1 results are often used in
2457 conditional or looping commands, for example:
2459 if {![file exists foo]} {
2460 error {bad file name}
2467 +*finalize* 'reference ?command?'+
2469 If +'command'+ is omitted, returns the finalizer command for the given reference.
2471 Otherwise, sets a new finalizer command for the given reference. +'command'+ may be
2472 the empty string to remove the current finalizer.
2474 The reference must be a valid reference create with the `ref`
2477 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2485 Flushes any output that has been buffered for +'fileId'+. +'fileId'+ must
2486 have been the return value from a previous call to `open`, or it may be
2487 +stdout+ or +stderr+ to access one of the standard I/O streams; it must
2488 refer to a file that was opened for writing. This command returns an
2493 +*for* 'start test next body'+
2495 `for` is a looping command, similar in structure to the C `for` statement.
2496 The +'start'+, +'next'+, and +'body'+ arguments must be Tcl command strings,
2497 and +'test'+ is an expression string.
2499 The `for` command first invokes the Tcl interpreter to execute +'start'+.
2500 Then it repeatedly evaluates +'test'+ as an expression; if the result is
2501 non-zero it invokes the Tcl interpreter on +'body'+, then invokes the Tcl
2502 interpreter on +'next'+, then repeats the loop. The command terminates
2503 when +'test'+ evaluates to 0.
2505 If a `continue` command is invoked within +'body'+ then any remaining
2506 commands in the current execution of +'body'+ are skipped; processing
2507 continues by invoking the Tcl interpreter on +'next'+, then evaluating
2508 +'test'+, and so on.
2510 If a `break` command is invoked within +'body'+ or +'next'+, then the `for`
2511 command will return immediately.
2513 The operation of `break` and `continue` are similar to the corresponding
2516 `for` returns an empty string.
2520 +*foreach* 'varName list body'+
2522 +*foreach* 'varList list ?varList2 list2 \...? body'+
2524 In this command, +'varName'+ is the name of a variable, +'list'+
2525 is a list of values to assign to +'varName'+, and +'body'+ is a
2526 collection of Tcl commands.
2528 For each field in +'list'+ (in order from left to right), `foreach` assigns
2529 the contents of the field to +'varName'+ (as if the `lindex` command
2530 had been used to extract the field), then calls the Tcl interpreter to
2533 If instead of being a simple name, +'varList'+ is used, multiple assignments
2534 are made each time through the loop, one for each element of +'varList'+.
2536 For example, if there are two elements in +'varList'+ and six elements in
2537 the list, the loop will be executed three times.
2539 If the length of the list doesn't evenly divide by the number of elements
2540 in +'varList'+, the value of the remaining variables in the last iteration
2541 of the loop are undefined.
2543 The `break` and `continue` statements may be invoked inside +'body'+,
2544 with the same effect as in the `for` command.
2546 `foreach` returns an empty string.
2550 +*format* 'formatString ?arg \...?'+
2552 This command generates a formatted string in the same way as the
2553 C 'sprintf' procedure (it uses 'sprintf' in its
2554 implementation). +'formatString'+ indicates how to format
2555 the result, using +%+ fields as in 'sprintf', and the additional
2556 arguments, if any, provide values to be substituted into the result.
2558 All of the 'sprintf' options are valid; see the 'sprintf'
2559 man page for details. Each +'arg'+ must match the expected type
2560 from the +%+ field in +'formatString'+; the `format` command
2561 converts each argument to the correct type (floating, integer, etc.)
2562 before passing it to 'sprintf' for formatting.
2564 The only unusual conversion is for +%c+; in this case the argument
2565 must be a decimal string, which will then be converted to the corresponding
2566 ASCII (or UTF-8) character value.
2568 In addition, Jim Tcl provides basic support for conversion to binary with +%b+.
2570 `format` does backslash substitution on its +'formatString'+
2571 argument, so backslash sequences in +'formatString'+ will be handled
2572 correctly even if the argument is in braces.
2574 The return value from `format` is the formatted string.
2578 +*getref* 'reference'+
2580 Returns the string associated with +'reference'+. The reference must
2581 be a valid reference create with the `ref` command.
2583 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2587 +*gets* 'fileId ?varName?'+
2589 +'fileId' *gets* '?varName?'+
2591 Reads the next line from the file given by +'fileId'+ and discards
2592 the terminating newline character.
2594 If +'varName'+ is specified, then the line is placed in the variable
2595 by that name and the return value is a count of the number of characters
2596 read (not including the newline).
2598 If the end of the file is reached before reading
2599 any characters then -1 is returned and +'varName'+ is set to an
2602 If +'varName'+ is not specified then the return value will be
2603 the line (minus the newline character) or an empty string if
2604 the end of the file is reached before reading any characters.
2606 An empty string will also be returned if a line contains no characters
2607 except the newline, so `eof` may have to be used to determine
2608 what really happened.
2610 If the last character in the file is not a newline character, then
2611 `gets` behaves as if there were an additional newline character
2612 at the end of the file.
2614 +'fileId'+ must be +stdin+ or the return value from a previous
2615 call to `open`; it must refer to a file that was opened
2620 +*glob* ?*-nocomplain*? ?*-directory* 'dir'? ?*-tails*? ?*--*? 'pattern ?pattern \...?'+
2622 This command performs filename globbing, using csh rules. The returned
2623 value from `glob` is the list of expanded filenames.
2625 If +-nocomplain+ is specified as the first argument then an empty
2626 list may be returned; otherwise an error is returned if the expanded
2627 list is empty. The +-nocomplain+ argument must be provided
2628 exactly: an abbreviation will not be accepted.
2630 If +-directory+ is given, the +'dir'+ is understood to contain a
2631 directory name to search in. This allows globbing inside directories
2632 whose names may contain glob-sensitive characters. The returned names
2633 include the directory name unless +'-tails'+ is specified.
2635 If +'-tails'+ is specified, along with +-directory+, the returned names
2636 are relative to the given directory.
2641 +*global* 'varName ?varName \...?'+
2643 This command is ignored unless a Tcl procedure is being interpreted.
2644 If so, then it declares each given +'varName'+ to be a global variable
2645 rather than a local one. For the duration of the current procedure
2646 (and only while executing in the current procedure), any reference to
2647 +'varName'+ will be bound to a global variable instead
2650 An alternative to using `global` is to use the +::+ prefix
2651 to explicitly name a variable in the global scope.
2655 +*if* 'expr1' ?*then*? 'body1' *elseif* 'expr2' ?*then*? 'body2' *elseif* \... ?*else*? ?'bodyN'?+
2657 The `if` command evaluates +'expr1'+ as an expression (in the same way
2658 that `expr` evaluates its argument). The value of the expression must
2659 be numeric; if it is non-zero then +'body1'+ is executed by passing it to
2660 the Tcl interpreter.
2662 Otherwise +'expr2'+ is evaluated as an expression and if it is non-zero
2663 then +'body2'+ is executed, and so on.
2665 If none of the expressions evaluates to non-zero then +'bodyN'+ is executed.
2667 The +then+ and +else+ arguments are optional "noise words" to make the
2668 command easier to read.
2670 There may be any number of +elseif+ clauses, including zero. +'bodyN'+
2671 may also be omitted as long as +else+ is omitted too.
2673 The return value from the command is the result of the body script that
2674 was executed, or an empty string if none of the expressions was non-zero
2675 and there was no +'bodyN'+.
2679 +*incr* 'varName ?increment?'+
2681 Increment the value stored in the variable whose name is +'varName'+.
2682 The value of the variable must be integral.
2684 If +'increment'+ is supplied then its value (which must be an
2685 integer) is added to the value of variable +'varName'+; otherwise
2686 1 is added to +'varName'+.
2688 The new value is stored as a decimal string in variable +'varName'+
2689 and also returned as result.
2691 If the variable does not exist, the variable is implicitly created
2692 and set to +0+ first.
2697 +*info* 'option ?arg\...?'+::
2699 Provide information about various internals to the Tcl interpreter.
2700 The legal +'option'+'s (which may be abbreviated) are:
2702 +*info args* 'procname'+::
2703 Returns a list containing the names of the arguments to procedure
2704 +'procname'+, in order. +'procname'+ must be the name of a
2705 Tcl command procedure.
2707 +*info alias* 'command'+::
2708 +'command'+ must be an alias created with `alias`. In which case the target
2709 command and arguments, as passed to `alias` are returned. See `exists -alias`
2711 +*info body* 'procname'+::
2712 Returns the body of procedure +'procname'+. +'procname'+ must be
2713 the name of a Tcl command procedure.
2716 Returns a list of all open file handles from `open` or `socket`
2718 +*info commands* ?'pattern'?+::
2719 If +'pattern'+ isn't specified, returns a list of names of all the
2720 Tcl commands, including both the built-in commands written in C and
2721 the command procedures defined using the `proc` command.
2722 If +'pattern'+ is specified, only those names matching +'pattern'+
2723 are returned. Matching is determined using the same rules as for
2726 +*info complete* 'command' ?'missing'?+::
2727 Returns 1 if +'command'+ is a complete Tcl command in the sense of
2728 having no unclosed quotes, braces, brackets or array element names,
2729 If the command doesn't appear to be complete then 0 is returned.
2730 This command is typically used in line-oriented input environments
2731 to allow users to type in commands that span multiple lines; if the
2732 command isn't complete, the script can delay evaluating it until additional
2733 lines have been typed to complete the command. If +'varName'+ is specified, the
2734 missing character is stored in the variable with that name.
2736 +*info exists* 'varName'+::
2737 Returns '1' if the variable named +'varName'+ exists in the
2738 current context (either as a global or local variable), returns '0'
2741 +*info frame* ?'number'?+::
2742 If +'number'+ is not specified, this command returns a number
2743 which is the same result as `info level` - the current stack frame level.
2744 If +'number'+ is specified, then the result is a list consisting of the procedure,
2745 filename and line number for the procedure call at level +'number'+ on the stack.
2746 If +'number'+ is positive then it selects a particular stack level (1 refers
2747 to the top-most active procedure, 2 to the procedure it called, and
2748 so on); otherwise it gives a level relative to the current level
2749 (0 refers to the current procedure, -1 to its caller, and so on).
2750 The level has an identical meaning to `info level`.
2752 +*info globals* ?'pattern'?+::
2753 If +'pattern'+ isn't specified, returns a list of all the names
2754 of currently-defined global variables.
2755 If +'pattern'+ is specified, only those names matching +'pattern'+
2756 are returned. Matching is determined using the same rules as for
2760 An alias for `os.gethostname` for compatibility with Tcl 6.x
2762 +*info level* ?'number'?+::
2763 If +'number'+ is not specified, this command returns a number
2764 giving the stack level of the invoking procedure, or 0 if the
2765 command is invoked at top-level. If +'number'+ is specified,
2766 then the result is a list consisting of the name and arguments for the
2767 procedure call at level +'number'+ on the stack. If +'number'+
2768 is positive then it selects a particular stack level (1 refers
2769 to the top-most active procedure, 2 to the procedure it called, and
2770 so on); otherwise it gives a level relative to the current level
2771 (0 refers to the current procedure, -1 to its caller, and so on).
2772 See the `uplevel` command for more information on what stack
2775 +*info locals* ?'pattern'?+::
2776 If +'pattern'+ isn't specified, returns a list of all the names
2777 of currently-defined local variables, including arguments to the
2778 current procedure, if any. Variables defined with the `global`
2779 and `upvar` commands will not be returned. If +'pattern'+ is
2780 specified, only those names matching +'pattern'+ are returned.
2781 Matching is determined using the same rules as for `string match`.
2783 +*info nameofexecutable*+::
2784 Returns the name of the binary file from which the application
2785 was invoked. A full path will be returned, unless the path
2786 can't be determined, in which case the empty string will be returned.
2788 +*info procs* ?'pattern'?+::
2789 If +'pattern'+ isn't specified, returns a list of all the
2790 names of Tcl command procedures.
2791 If +'pattern'+ is specified, only those names matching +'pattern'+
2792 are returned. Matching is determined using the same rules as for
2795 +*info references*+::
2796 Returns a list of all references which have not yet been garbage
2799 +*info returncodes* ?'code'?+::
2800 Returns a list representing the mapping of standard return codes
2801 to names. e.g. +{0 ok 1 error 2 return \...}+. If a code is given,
2802 instead returns the name for the given code.
2805 If a Tcl script file is currently being evaluated (i.e. there is a
2806 call to 'Jim_EvalFile' active or there is an active invocation
2807 of the `source` command), then this command returns the name
2808 of the innermost file being processed. Otherwise the command returns an
2811 +*info source* 'script ?filename line?'+::
2812 With a single argument, returns the original source location of the given script as a list of
2813 +{filename linenumber}+. If the source location can't be determined, the
2814 list +{{} 0}+ is returned. If +'filename'+ and +'line'+ are given, returns a copy
2815 of +'script'+ with the associate source information. This can be useful to produce
2816 useful messages from `eval`, etc. if the original source information may be lost.
2818 +*info stacktrace*+::
2819 After an error is caught with `catch`, returns the stack trace as a list
2820 of +{procedure filename line \...}+.
2822 +*info statics* 'procname'+::
2823 Returns a dictionary of the static variables of procedure
2824 +'procname'+. +'procname'+ must be the name of a Tcl command
2825 procedure. An empty dictionary is returned if the procedure has
2826 no static variables.
2829 Returns the version number for this version of Jim in the form +*x.yy*+.
2831 +*info vars* ?'pattern'?+::
2832 If +'pattern'+ isn't specified,
2833 returns a list of all the names of currently-visible variables, including
2834 both locals and currently-visible globals.
2835 If +'pattern'+ is specified, only those names matching +'pattern'+
2836 are returned. Matching is determined using the same rules as for
2841 +*join* 'list ?joinString?'+
2843 The +'list'+ argument must be a valid Tcl list. This command returns the
2844 string formed by joining all of the elements of +'list'+ together with
2845 +'joinString'+ separating each adjacent pair of elements.
2847 The +'joinString'+ argument defaults to a space character.
2851 +*kill* ?'SIG'|*-0*? 'pid'+
2853 Sends the given signal to the process identified by +'pid'+.
2855 The signal may be specified by name or number in one of the following forms:
2863 The signal name may be in either upper or lower case.
2865 The special signal name +-0+ simply checks that a signal +'could'+ be sent.
2867 If no signal is specified, SIGTERM is used.
2869 An error is raised if the signal could not be delivered.
2873 +*lambda* 'args ?statics? body'+
2875 The `lambda` command is identical to `proc`, except rather than
2876 creating a named procedure, it creates an anonymous procedure and returns
2877 the name of the procedure.
2879 See `proc` and GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2883 +*lappend* 'varName value ?value value \...?'+
2885 Treat the variable given by +'varName'+ as a list and append each of
2886 the +'value'+ arguments to that list as a separate element, with spaces
2889 If +'varName'+ doesn't exist, it is created as a list with elements given
2890 by the +'value'+ arguments. `lappend` is similar to `append` except that
2891 each +'value'+ is appended as a list element rather than raw text.
2893 This command provides a relatively efficient way to build up large lists.
2898 is much more efficient than
2900 set a [concat $a [list $b]]
2906 +*lassign* 'list varName ?varName \...?'+
2908 This command treats the value +'list'+ as a list and assigns successive elements from that list to
2909 the variables given by the +'varName'+ arguments in order. If there are more variable names than
2910 list elements, the remaining variables are set to the empty string. If there are more list elements
2911 than variables, a list of unassigned elements is returned.
2913 jim> lassign {1 2 3} a b; puts a=$a,b=$b
2919 +*local* 'cmd ?arg\...?'+
2921 First, `local` evaluates +'cmd'+ with the given arguments. The return value must
2922 be the name of an existing command, which is marked as having local scope.
2923 This means that when the current procedure exits, the specified
2924 command is deleted. This can be useful with `lambda`, local procedures or
2925 to automatically close a filehandle.
2927 In addition, if a command already exists with the same name,
2928 the existing command will be kept rather than deleted, and may be called
2929 via `upcall`. The previous command will be restored when the current
2930 procedure exits. See `upcall` for more details.
2932 In this example, a local procedure is created. Note that the procedure
2933 continues to have global scope while it is active.
2936 # proc ... returns "inner" which is marked local
2937 local proc inner {} {
2938 # will be deleted when 'outer' exits
2945 In this example, the lambda is deleted at the end of the procedure rather
2946 than waiting until garbage collection.
2949 set x [lambda inner {args} {
2950 # will be deleted when 'outer' exits
2952 # Use 'function' here which simply returns $x
2961 +*loop* 'var first limit ?incr? body'+
2963 Similar to `for` except simpler and possibly more efficient.
2964 With a positive increment, equivalent to:
2966 for {set var $first} {$var < $limit} {incr var $incr} $body
2968 If +'incr'+ is not specified, 1 is used.
2969 Note that setting the loop variable inside the loop does not
2970 affect the loop count.
2974 +*lindex* 'list ?index ...?'+
2976 Treats +'list'+ as a Tcl list and returns element +'index'+ from it
2977 (0 refers to the first element of the list).
2978 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
2980 In extracting the element, +'lindex'+ observes the same rules concerning
2981 braces and quotes and backslashes as the Tcl command interpreter; however,
2982 variable substitution and command substitution do not occur.
2984 If no index values are given, simply returns +'list'+
2986 If +'index'+ is negative or greater than or equal to the number of elements
2987 in +'list'+, then an empty string is returned.
2989 If additional index arguments are supplied, then each argument is
2990 used in turn to select an element from the previous indexing
2991 operation, allowing the script to select elements from sublists.
2995 +*linsert* 'list index element ?element element \...?'+
2997 This command produces a new list from +'list'+ by inserting all
2998 of the +'element'+ arguments just before the element +'index'+
2999 of +'list'+. Each +'element'+ argument will become
3000 a separate element of the new list. If +'index'+ is less than
3001 or equal to zero, then the new elements are inserted at the
3002 beginning of the list. If +'index'+ is greater than or equal
3003 to the number of elements in the list, then the new elements are
3004 appended to the list.
3006 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
3011 +*list* 'arg ?arg \...?'+
3013 This command returns a list comprised of all the arguments, +'arg'+. Braces
3014 and backslashes get added as necessary, so that the `lindex` command
3015 may be used on the result to re-extract the original arguments, and also
3016 so that `eval` may be used to execute the resulting list, with
3017 +'arg1'+ comprising the command's name and the other args comprising
3018 its arguments. `list` produces slightly different results than
3019 `concat`: `concat` removes one level of grouping before forming
3020 the list, while `list` works directly from the original arguments.
3021 For example, the command
3023 list a b {c d e} {f {g h}}
3027 a b {c d e} {f {g h}}
3029 while `concat` with the same arguments will return
3037 Treats +'list'+ as a list and returns a decimal string giving
3038 the number of elements in it.
3042 +*lset* 'varName ?index ..? newValue'+
3044 Sets an element in a list.
3046 The `lset` command accepts a parameter, +'varName'+, which it interprets
3047 as the name of a variable containing a Tcl list. It also accepts
3048 zero or more indices into the list. Finally, it accepts a new value
3049 for an element of varName. If no indices are presented, the command
3052 lset varName newValue
3054 In this case, newValue replaces the old value of the variable
3057 When presented with a single index, the `lset` command
3058 treats the content of the varName variable as a Tcl list. It addresses
3059 the index'th element in it (0 refers to the first element of the
3060 list). When interpreting the list, `lset` observes the same rules
3061 concerning braces and quotes and backslashes as the Tcl command
3062 interpreter; however, variable substitution and command substitution
3063 do not occur. The command constructs a new list in which the
3064 designated element is replaced with newValue. This new list is
3065 stored in the variable varName, and is also the return value from
3068 If index is negative or greater than or equal to the number of
3069 elements in $varName, then an error occurs.
3071 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
3073 If additional index arguments are supplied, then each argument is
3074 used in turn to address an element within a sublist designated by
3075 the previous indexing operation, allowing the script to alter
3076 elements in sublists. The command,
3080 replaces element 2 of sublist 1 with +'newValue'+.
3082 The integer appearing in each index argument must be greater than
3083 or equal to zero. The integer appearing in each index argument must
3084 be strictly less than the length of the corresponding list. In other
3085 words, the `lset` command cannot change the size of a list. If an
3086 index is outside the permitted range, an error is reported.
3091 +*lmap* 'varName list body'+
3093 +*lmap* 'varList list ?varList2 list2 \...? body'+
3095 `lmap` is a "collecting" `foreach` which returns a list of its results.
3099 jim> lmap i {1 2 3 4 5} {expr $i*$i}
3101 jim> lmap a {1 2 3} b {A B C} {list $a $b}
3104 If the body invokes `continue`, no value is added for this iteration.
3105 If the body invokes `break`, the loop ends and no more values are added.
3111 Loads the dynamic extension, +'filename'+. Generally the filename should have
3112 the extension +.so+. The initialisation function for the module must be based
3113 on the name of the file. For example loading +hwaccess.so+ will invoke
3114 the initialisation function, +Jim_hwaccessInit+. Normally the `load` command
3115 should not be used directly. Instead it is invoked automatically by `package require`.
3119 +*lrange* 'list first last'+
3121 +'list'+ must be a valid Tcl list. This command will return a new
3122 list consisting of elements +'first'+ through +'last'+, inclusive.
3124 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
3126 If +'last'+ is greater than or equal to the number of elements
3127 in the list, then it is treated as if it were +end+.
3129 If +'first'+ is greater than +'last'+ then an empty string
3132 Note: +"`lrange` 'list first first'"+ does not always produce the
3133 same result as +"`lindex` 'list first'"+ (although it often does
3134 for simple fields that aren't enclosed in braces); it does, however,
3135 produce exactly the same results as +"`list` [`lindex` 'list first']"+
3140 +*lreplace* 'list first last ?element element \...?'+
3142 Returns a new list formed by replacing one or more elements of
3143 +'list'+ with the +'element'+ arguments.
3145 +'first'+ gives the index in +'list'+ of the first element
3148 If +'first'+ is less than zero then it refers to the first
3149 element of +'list'+; the element indicated by +'first'+
3150 must exist in the list.
3152 +'last'+ gives the index in +'list'+ of the last element
3153 to be replaced; it must be greater than or equal to +'first'+.
3155 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
3157 The +'element'+ arguments specify zero or more new arguments to
3158 be added to the list in place of those that were deleted.
3160 Each +'element'+ argument will become a separate element of
3163 If no +'element'+ arguments are specified, then the elements
3164 between +'first'+ and +'last'+ are simply deleted.
3168 +*lrepeat* 'number element1 ?element2 \...?'+
3170 Build a list by repeating elements +'number'+ times (which must be
3171 a positive integer).
3180 Returns the list in reverse order.
3182 jim> lreverse {1 2 3}
3187 +*lsearch* '?options? list pattern'+
3189 This command searches the elements +'list'+ to see if one of them matches +'pattern'+. If so, the
3190 command returns the index of the first matching element (unless the options +-all+, +-inline+ or +-bool+ are
3191 specified.) If not, the command returns -1. The option arguments indicates how the elements of
3192 the list are to be matched against pattern and must have one of the values below:
3194 *Note* that this command is different from Tcl in that default match type is +-exact+ rather than +-glob+.
3197 +'pattern'+ is a literal string that is compared for exact equality against each list element.
3198 This is the default.
3201 +'pattern'+ is a glob-style pattern which is matched against each list element using the same
3202 rules as the string match command.
3205 +'pattern'+ is treated as a regular expression and matched against each list element using
3206 the rules described by `regexp`.
3208 +*-command* 'cmdname'+::
3209 +'cmdname'+ is a command which is used to match the pattern against each element of the
3210 list. It is invoked as +'cmdname' ?*-nocase*? 'pattern listvalue'+ and should return 1
3211 for a match, or 0 for no match.
3214 Changes the result to be the list of all matching indices (or all matching values if
3215 +-inline+ is specified as well). If indices are returned, the indices will be in numeric
3216 order. If values are returned, the order of the values will be the order of those values
3217 within the input list.
3220 The matching value is returned instead of its index (or an empty string if no value
3221 matches). If +-all+ is also specified, then the result of the command is the list of all
3222 values that matched. The +-inline+ and +-bool+ options are mutually exclusive.
3225 Changes the result to '1' if a match was found, or '0' otherwise. If +-all+ is also specified,
3226 the result will be a list of '0' and '1' for each element of the list depending upon whether
3227 the corresponding element matches. The +-inline+ and +-bool+ options are mutually exclusive.
3230 This negates the sense of the match, returning the index (or value
3231 if +-inline+ is specified) of the first non-matching value in the
3232 list. If +-bool+ is also specified, the '0' will be returned if a
3233 match is found, or '1' otherwise. If +-all+ is also specified,
3234 non-matches will be returned rather than matches.
3237 Causes comparisons to be handled in a case-insensitive manner.
3241 +*lsort* ?*-index* 'listindex'? ?*-nocase|-integer|-real|-command* 'cmdname'? ?*-unique*? ?*-decreasing*|*-increasing*? 'list'+
3243 Sort the elements of +'list'+, returning a new list in sorted order.
3244 By default, ASCII (or UTF-8) sorting is used, with the result in increasing order.
3246 If +-nocase+ is specified, comparisons are case-insensitive.
3248 If +-integer+ is specified, numeric sorting is used.
3250 If +-real+ is specified, floating point number sorting is used.
3252 If +-command 'cmdname'+ is specified, +'cmdname'+ is treated as a command
3253 name. For each comparison, +'cmdname $value1 $value2+' is called which
3254 should compare the values and return an integer less than, equal
3255 to, or greater than zero if the +'$value1'+ is to be considered less
3256 than, equal to, or greater than +'$value2'+, respectively.
3258 If +-decreasing+ is specified, the resulting list is in the opposite
3259 order to what it would be otherwise. +-increasing+ is the default.
3261 If +-unique+ is specified, then only the last set of duplicate elements found in the list will be retained.
3262 Note that duplicates are determined relative to the comparison used in the sort. Thus if +-index 0+ is used,
3263 +{1 a}+ and +{1 b}+ would be considered duplicates and only the second element, +{1 b}+, would be retained.
3265 If +-index 'listindex'+ is specified, each element of the list is treated as a list and
3266 the given index is extracted from the list for comparison. The list index may
3267 be any valid list index, such as +1+, +end+ or +end-2+.
3273 This command is a simple helper command to add a script to the '+$jim::defer+' variable
3274 that will run when the current proc or interpreter exits. For example:
3276 jim> proc a {} { defer {puts "Leaving a"}; puts "Exit" }
3281 If the '+$jim::defer+' variable exists, it is treated as a list of scripts to run
3282 when the proc or interpreter exits.
3286 +*open* 'fileName ?access?'+
3288 +*open* '|command-pipeline ?access?'+
3290 Opens a file and returns an identifier
3291 that may be used in future invocations
3292 of commands like `read`, `puts`, and `close`.
3293 +'fileName'+ gives the name of the file to open.
3295 The +'access'+ argument indicates the way in which the file is to be accessed.
3296 It may have any of the following values:
3299 Open the file for reading only; the file must already exist.
3302 Open the file for both reading and writing; the file must
3306 Open the file for writing only. Truncate it if it exists. If it doesn't
3307 exist, create a new file.
3310 Open the file for reading and writing. Truncate it if it exists.
3311 If it doesn't exist, create a new file.
3314 Open the file for writing only. The file must already exist, and the file
3315 is positioned so that new data is appended to the file.
3318 Open the file for reading and writing. If the file doesn't
3319 exist, create a new empty file. Set the initial access position
3320 to the end of the file.
3322 +'access'+ defaults to 'r'.
3324 If a file is opened for both reading and writing, then `seek`
3325 must be invoked between a read and a write, or vice versa.
3327 If the first character of +'fileName'+ is "|" then the remaining
3328 characters of +'fileName'+ are treated as a list of arguments that
3329 describe a command pipeline to invoke, in the same style as the
3330 arguments for exec. In this case, the channel identifier returned
3331 by open may be used to write to the command's input pipe or read
3332 from its output pipe, depending on the value of +'access'+. If write-only
3333 access is used (e.g. +'access'+ is 'w'), then standard output for the
3334 pipeline is directed to the current standard output unless overridden
3335 by the command. If read-only access is used (e.g. +'access'+ is r),
3336 standard input for the pipeline is taken from the current standard
3337 input unless overridden by the command.
3339 The `pid` command may be used to return the process ids of the commands
3340 forming the command pipeline.
3342 See also `socket`, `pid`, `exec`
3346 +*package provide* 'name ?version?'+
3348 Indicates that the current script provides the package named +'name'+.
3349 If no version is specified, '1.0' is used.
3351 Any script which provides a package may include this statement
3352 as the first statement, although it is not required.
3354 +*package require* 'name ?version?'*+
3356 Searches for the package with the given +'name'+ by examining each path
3357 in '$::auto_path' and trying to load '$path/$name.so' as a dynamic extension,
3358 or '$path/$name.tcl' as a script package.
3360 The first such file which is found is considered to provide the package.
3361 (The version number is ignored).
3363 If '$name.so' exists, it is loaded with the `load` command,
3364 otherwise if '$name.tcl' exists it is loaded with the `source` command.
3366 If `load` or `source` fails, `package require` will fail immediately.
3367 No further attempt will be made to locate the file.
3375 The first form returns the process identifier of the current process.
3377 The second form accepts a handle returned by `open` and returns a list
3378 of the process ids forming the pipeline in the same form as `exec ... &`.
3379 If 'fileId' represents a regular file handle rather than a command pipeline,
3380 the empty string is returned instead.
3382 See also `open`, `exec`
3386 +*proc* 'name args ?statics? body'+
3388 The `proc` command creates a new Tcl command procedure, +'name'+.
3389 When the new command is invoked, the contents of +'body'+ will be executed.
3390 Tcl interpreter. +'args'+ specifies the formal arguments to the procedure.
3391 If specified, +'statics'+, declares static variables which are bound to the
3394 See PROCEDURES for detailed information about Tcl procedures.
3396 The `proc` command returns +'name'+ (which is useful with `local`).
3398 When a procedure is invoked, the procedure's return value is the
3399 value specified in a `return` command. If the procedure doesn't
3400 execute an explicit `return`, then its return value is the value
3401 of the last command executed in the procedure's body.
3403 If an error occurs while executing the procedure body, then the
3404 procedure-as-a-whole will return that same error.
3408 +*puts* ?*-nonewline*? '?fileId? string'+
3410 +'fileId' *puts* ?*-nonewline*? 'string'+
3412 Writes the characters given by +'string'+ to the file given
3413 by +'fileId'+. +'fileId'+ must have been the return
3414 value from a previous call to `open`, or it may be
3415 +stdout+ or +stderr+ to refer to one of the standard I/O
3416 channels; it must refer to a file that was opened for
3419 In the first form, if no +'fileId'+ is specified then it defaults to +stdout+.
3420 `puts` normally outputs a newline character after +'string'+,
3421 but this feature may be suppressed by specifying the +-nonewline+
3424 Output to files is buffered internally by Tcl; the `flush`
3425 command may be used to force buffered characters to be output.
3429 Creates a pair of `aio` channels and returns the handles as a list: +{read write}+
3433 # Must close $w after exec
3443 Returns the path name of the current working directory.
3447 +*rand* '?min? ?max?'+
3449 Returns a random integer between +'min'+ (defaults to 0) and +'max'+
3450 (defaults to the maximum integer).
3452 If only one argument is given, it is interpreted as +'max'+.
3456 +*range* '?start? end ?step?'+
3458 Returns a list of integers starting at +'start'+ (defaults to 0)
3459 and ranging up to but not including +'end'+ in steps of +'step'+ defaults to 1).
3472 +*read* ?*-nonewline*? 'fileId'+
3474 +'fileId' *read* ?*-nonewline*?+
3476 +*read* 'fileId numBytes'+
3478 +'fileId' *read* 'numBytes'+
3481 In the first form, all of the remaining bytes are read from the file
3482 given by +'fileId'+; they are returned as the result of the command.
3483 If the +-nonewline+ switch is specified then the last
3484 character of the file is discarded if it is a newline.
3486 In the second form, the extra argument specifies how many bytes to read;
3487 exactly this many bytes will be read and returned, unless there are fewer than
3488 +'numBytes'+ bytes left in the file; in this case, all the remaining
3491 +'fileId'+ must be +stdin+ or the return value from a previous call
3492 to `open`; it must refer to a file that was opened for reading.
3496 +*regexp ?-nocase? ?-line? ?-indices? ?-start* 'offset'? *?-all? ?-inline? ?--?* 'exp string ?matchVar? ?subMatchVar subMatchVar \...?'+
3498 Determines whether the regular expression +'exp'+ matches part or
3499 all of +'string'+ and returns 1 if it does, 0 if it doesn't.
3501 See REGULAR EXPRESSIONS above for complete information on the
3502 syntax of +'exp'+ and how it is matched against +'string'+.
3504 If additional arguments are specified after +'string'+ then they
3505 are treated as the names of variables to use to return
3506 information about which part(s) of +'string'+ matched +'exp'+.
3507 +'matchVar'+ will be set to the range of +'string'+ that
3508 matched all of +'exp'+. The first +'subMatchVar'+ will contain
3509 the characters in +'string'+ that matched the leftmost parenthesized
3510 subexpression within +'exp'+, the next +'subMatchVar'+ will
3511 contain the characters that matched the next parenthesized
3512 subexpression to the right in +'exp'+, and so on.
3514 Normally, +'matchVar'+ and the each +'subMatchVar'+ are set to hold the
3515 matching characters from `string`, however see +-indices+ and
3518 If there are more values for +'subMatchVar'+ than parenthesized subexpressions
3519 within +'exp'+, or if a particular subexpression in +'exp'+ doesn't
3520 match the string (e.g. because it was in a portion of the expression
3521 that wasn't matched), then the corresponding +'subMatchVar'+ will be
3522 set to +"-1 -1"+ if +-indices+ has been specified or to an empty
3525 The following switches modify the behaviour of +'regexp'+
3528 Causes upper-case and lower-case characters to be treated as
3529 identical during the matching process.
3532 Use newline-sensitive matching. By default, newline
3533 is a completely ordinary character with no special meaning in
3534 either REs or strings. With this flag, +[^+ bracket expressions
3535 and +.+ never match newline, an +^+ anchor matches the null
3536 string after any newline in the string in addition to its normal
3537 function, and the +$+ anchor matches the null string before any
3538 newline in the string in addition to its normal function.
3541 Changes what is stored in the subMatchVars. Instead of
3542 storing the matching characters from string, each variable
3543 will contain a list of two decimal strings giving the indices
3544 in string of the first and last characters in the matching
3545 range of characters.
3547 +*-start* 'offset'+::
3548 Specifies a character index offset into the string at which to start
3549 matching the regular expression. If +-indices+ is
3550 specified, the indices will be indexed starting from the
3551 absolute beginning of the input string. +'offset'+ will be
3552 constrained to the bounds of the input string.
3555 Causes the regular expression to be matched as many times as possible
3556 in the string, returning the total number of matches found. If this
3557 is specified with match variables, they will contain information
3558 for the last match only.
3561 Causes the command to return, as a list, the data that would otherwise
3562 be placed in match variables. When using +-inline+, match variables
3563 may not be specified. If used with +-all+, the list will be concatenated
3564 at each iteration, such that a flat list is always returned. For
3565 each match iteration, the command will append the overall match
3566 data, plus one element for each subexpression in the regular
3570 Marks the end of switches. The argument following this one will be
3571 treated as +'exp'+ even if it starts with a +-+.
3575 +*regsub ?-nocase? ?-all? ?-line? ?-start* 'offset'? ?*--*? 'exp string subSpec ?varName?'+
3577 This command matches the regular expression +'exp'+ against
3578 +'string'+ using the rules described in REGULAR EXPRESSIONS
3581 If +'varName'+ is specified, the commands stores +'string'+ to +'varName'+
3582 with the substitutions detailed below, and returns the number of
3583 substitutions made (normally 1 unless +-all+ is specified).
3584 This is 0 if there were no matches.
3586 If +'varName'+ is not specified, the substituted string will be returned
3589 When copying +'string'+, the portion of +'string'+ that
3590 matched +'exp'+ is replaced with +'subSpec'+.
3591 If +'subSpec'+ contains a +&+ or +{backslash}0+, then it is replaced
3592 in the substitution with the portion of +'string'+ that
3595 If +'subSpec'+ contains a +{backslash}n+, where +'n'+ is a digit
3596 between 1 and 9, then it is replaced in the substitution with
3597 the portion of +'string'+ that matched the +'n'+\'-th
3598 parenthesized subexpression of +'exp'+.
3599 Additional backslashes may be used in +'subSpec'+ to prevent special
3600 interpretation of +&+ or +{backslash}0+ or +{backslash}n+ or
3603 The use of backslashes in +'subSpec'+ tends to interact badly
3604 with the Tcl parser's use of backslashes, so it's generally
3605 safest to enclose +'subSpec'+ in braces if it includes
3608 The following switches modify the behaviour of +'regsub'+
3611 Upper-case characters in +'string'+ are converted to lower-case
3612 before matching against +'exp'+; however, substitutions
3613 specified by +'subSpec'+ use the original unconverted form
3617 All ranges in +'string'+ that match +'exp'+ are found and substitution
3618 is performed for each of these ranges, rather than only the
3619 first. The +&+ and +{backslash}n+ sequences are handled for
3620 each substitution using the information from the corresponding
3624 Use newline-sensitive matching. By default, newline
3625 is a completely ordinary character with no special meaning in
3626 either REs or strings. With this flag, +[^+ bracket expressions
3627 and +.+ never match newline, an +^+ anchor matches the null
3628 string after any newline in the string in addition to its normal
3629 function, and the +$+ anchor matches the null string before any
3630 newline in the string in addition to its normal function.
3632 +*-start* 'offset'+::
3633 Specifies a character index offset into the string at which to
3634 start matching the regular expression. +'offset'+ will be
3635 constrained to the bounds of the input string.
3638 Marks the end of switches. The argument following this one will be
3639 treated as +'exp'+ even if it starts with a +-+.
3643 +*ref* 'string tag ?finalizer?'+
3645 Create a new reference containing +'string'+ of type +'tag'+.
3646 If +'finalizer'+ is specified, it is a command which will be invoked
3647 when the a garbage collection cycle runs and this reference is
3648 no longer accessible.
3650 The finalizer is invoked as:
3652 finalizer reference string
3654 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
3658 +*rename* 'oldName newName'+
3660 Rename the command that used to be called +'oldName'+ so that it
3661 is now called +'newName'+. If +'newName'+ is an empty string
3662 (e.g. {}) then +'oldName'+ is deleted. The `rename` command
3663 returns an empty string as result.
3667 +*return* ?*-code* 'code'? ?*-errorinfo* 'stacktrace'? ?*-errorcode* 'errorcode'? ?*-level* 'n'? ?'value'?+
3669 Return immediately from the current procedure (or top-level command
3670 or `source` command), with +'value'+ as the return value. If +'value'+
3671 is not specified, an empty string will be returned as result.
3673 If +-code+ is specified (as either a number or ok, error, break,
3674 continue, signal, return or exit), this code will be used instead
3675 of +JIM_OK+. This is generally useful when implementing flow of control
3678 If +-level+ is specified and greater than 1, it has the effect of delaying
3679 the new return code from +-code+. This is useful when rethrowing an error
3680 from `catch`. See the implementation of try/catch in tclcompat.tcl for
3681 an example of how this is done.
3683 Note: The following options are only used when +-code+ is JIM_ERR.
3685 If +-errorinfo+ is specified (as returned from `info stacktrace`)
3686 it is used to initialize the stacktrace.
3688 If +-errorcode+ is specified, it is used to set the global variable $::errorCode.
3692 +*scan* 'string format varName1 ?varName2 \...?'+
3694 This command parses fields from an input string in the same fashion
3695 as the C 'sscanf' procedure. +'string'+ gives the input to be parsed
3696 and +'format'+ indicates how to parse it, using '%' fields as in
3697 'sscanf'. All of the 'sscanf' options are valid; see the 'sscanf'
3698 man page for details. Each +'varName'+ gives the name of a variable;
3699 when a field is scanned from +'string'+, the result is converted back
3700 into a string and assigned to the corresponding +'varName'+. The
3701 only unusual conversion is for '%c'. For '%c' conversions a single
3702 character value is converted to a decimal string, which is then
3703 assigned to the corresponding +'varName'+; no field width may be
3704 specified for this conversion.
3708 +*seek* 'fileId offset ?origin?'+
3710 +'fileId' *seek* 'offset ?origin?'+
3712 Change the current access position for +'fileId'+.
3713 The +'offset'+ and +'origin'+ arguments specify the position at
3714 which the next read or write will occur for +'fileId'+.
3715 +'offset'+ must be a number (which may be negative) and +'origin'+
3716 must be one of the following:
3719 The new access position will be +'offset'+ bytes from the start
3723 The new access position will be +'offset'+ bytes from the current
3724 access position; a negative +'offset'+ moves the access position
3725 backwards in the file.
3728 The new access position will be +'offset'+ bytes from the end of
3729 the file. A negative +'offset'+ places the access position before
3730 the end-of-file, and a positive +'offset'+ places the access position
3731 after the end-of-file.
3733 The +'origin'+ argument defaults to +start+.
3735 +'fileId'+ must have been the return value from a previous call to
3736 `open`, or it may be +stdin+, +stdout+, or +stderr+ to refer to one
3737 of the standard I/O channels.
3739 This command returns an empty string.
3743 +*set* 'varName ?value?'+
3745 Returns the value of variable +'varName'+.
3747 If +'value'+ is specified, then set the value of +'varName'+ to +'value'+,
3748 creating a new variable if one doesn't already exist, and return
3751 If +'varName'+ contains an open parenthesis and ends with a
3752 close parenthesis, then it refers to an array element: the characters
3753 before the open parenthesis are the name of the array, and the characters
3754 between the parentheses are the index within the array.
3755 Otherwise +'varName'+ refers to a scalar variable.
3757 If no procedure is active, then +'varName'+ refers to a global
3760 If a procedure is active, then +'varName'+ refers to a parameter
3761 or local variable of the procedure, unless the +'global'+ command
3762 has been invoked to declare +'varName'+ to be global.
3764 The +::+ prefix may also be used to explicitly reference a variable
3765 in the global scope.
3769 +*setref* 'reference string'+
3771 Store a new string in +'reference'+, replacing the existing string.
3772 The reference must be a valid reference create with the `ref`
3775 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
3779 Command for signal handling.
3781 See `kill` for the different forms which may be used to specify signals.
3783 Commands which return a list of signal names do so using the canonical form:
3786 +*signal handle* ?'signals \...'?+::
3787 If no signals are given, returns a list of all signals which are currently
3789 If signals are specified, these are added to the list of signals currently
3792 +*signal ignore* ?'signals \...'?+::
3793 If no signals are given, returns a lists all signals which are currently
3795 If signals are specified, these are added to the list of signals
3796 currently being ignored. These signals are still delivered, but
3797 are not considered by `catch -signal` or `try -signal`. Use
3798 `signal check` to determine which signals have occurred but
3801 +*signal default* ?'signals \...'?+::
3802 If no signals are given, returns a lists all signals which are currently have
3803 the default behaviour.
3804 If signals are specified, these are added to the list of signals which have
3805 the default behaviour.
3807 +*signal check ?-clear?* ?'signals \...'?+::
3808 Returns a list of signals which have been delivered to the process
3809 but are 'ignored'. If signals are specified, only that set of signals will
3810 be checked, otherwise all signals will be checked.
3811 If +-clear+ is specified, any signals returned are removed and will not be
3812 returned by subsequent calls to `signal check` unless delivered again.
3814 +*signal throw* ?'signal'?+::
3815 Raises the given signal, which defaults to +SIGINT+ if not specified.
3816 The behaviour is identical to:
3820 Note that `signal handle` and `signal ignore` represent two forms of signal
3821 handling. `signal handle` is used in conjunction with `catch -signal` or `try -signal`
3822 to immediately abort execution when the signal is delivered. Alternatively, `signal ignore`
3823 is used in conjunction with `signal check` to handle signal synchronously. Consider the
3826 Prevent a processing from taking too long
3828 signal handle SIGALRM
3831 .. possibly long running process ..
3834 puts stderr "Process took too long"
3837 Handle SIGHUP to reconfigure:
3839 signal ignore SIGHUP
3841 ... handle configuration/reconfiguration ...
3842 while {[signal check -clear SIGHUP] eq ""} {
3843 ... do processing ..
3845 # Received SIGHUP, so reconfigure
3848 Note: signal handling is currently not supported in child interpreters.
3849 In these interpreters, the signal command does not exist.
3855 Pauses for the given number of seconds, which may be a floating
3856 point value less than one to sleep for less than a second, or an
3857 integer to sleep for one or more seconds.
3861 +*source* 'fileName'+
3863 Read file +'fileName'+ and pass the contents to the Tcl interpreter
3864 as a sequence of commands to execute in the normal fashion. The return
3865 value of `source` is the return value of the last command executed
3866 from the file. If an error occurs in executing the contents of the
3867 file, then the `source` command will return that error.
3869 If a `return` command is invoked from within the file, the remainder of
3870 the file will be skipped and the `source` command will return
3871 normally with the result from the `return` command.
3875 +*split* 'string ?splitChars?'+
3877 Returns a list created by splitting +'string'+ at each character
3878 that is in the +'splitChars'+ argument.
3880 Each element of the result list will consist of the
3881 characters from +'string'+ between instances of the
3882 characters in +'splitChars'+.
3884 Empty list elements will be generated if +'string'+ contains
3885 adjacent characters in +'splitChars'+, or if the first or last
3886 character of +'string'+ is in +'splitChars'+.
3888 If +'splitChars'+ is an empty string then each character of
3889 +'string'+ becomes a separate element of the result list.
3891 +'splitChars'+ defaults to the standard white-space characters.
3894 split "comp.unix.misc" .
3896 returns +'"comp unix misc"'+ and
3898 split "Hello world" {}
3900 returns +'"H e l l o { } w o r l d"'+.
3905 +*stackdump* 'stacktrace'+
3907 Creates a human readable representation of a stack trace.
3914 Returns a live stack trace as a list of +proc file line proc file line \...+.
3915 Iteratively uses `info frame` to create the stack trace. This stack trace is in the
3916 same form as produced by `catch` and `info stacktrace`
3918 See also `stackdump`.
3923 +*string* 'option arg ?arg \...?'+
3925 Perform one of several string operations, depending on +'option'+.
3926 The legal options (which may be abbreviated) are:
3928 +*string bytelength* 'string'+::
3929 Returns the length of the string in bytes. This will return
3930 the same value as `string length` if UTF-8 support is not enabled,
3931 or if the string is composed entirely of ASCII characters.
3932 See UTF-8 AND UNICODE.
3934 +*string byterange* 'string first last'+::
3935 Like `string range` except works on bytes rather than characters.
3936 These commands are identical if UTF-8 support is not enabled.
3938 +*string cat* '?string1 string2 \...?'+::
3939 Concatenates the given strings into a single string.
3941 +*string compare ?-nocase?* ?*-length* 'len? string1 string2'+::
3942 Perform a character-by-character comparison of strings +'string1'+ and
3943 +'string2'+ in the same way as the C 'strcmp' procedure. Return
3944 -1, 0, or 1, depending on whether +'string1'+ is lexicographically
3945 less than, equal to, or greater than +'string2'+. If +-length+
3946 is specified, then only the first +'len'+ characters are used
3947 in the comparison. If +'len'+ is negative, it is ignored.
3948 Performs a case-insensitive comparison if +-nocase+ is specified.
3950 +*string equal ?-nocase?* '?*-length* len?' 'string1 string2'+::
3951 Returns 1 if the strings are equal, or 0 otherwise. If +-length+
3952 is specified, then only the first +'len'+ characters are used
3953 in the comparison. If +'len'+ is negative, it is ignored.
3954 Performs a case-insensitive comparison if +-nocase+ is specified.
3956 +*string first* 'string1 string2 ?firstIndex?'+::
3957 Search +'string2'+ for a sequence of characters that exactly match
3958 the characters in +'string1'+. If found, return the index of the
3959 first character in the first such match within +'string2'+. If not
3960 found, return -1. If +'firstIndex'+ is specified, matching will start
3961 from +'firstIndex'+ of +'string1'+.
3963 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'firstIndex'+.
3965 +*string index* 'string charIndex'+::
3966 Returns the +'charIndex'+'th character of the +'string'+
3967 argument. A +'charIndex'+ of 0 corresponds to the first
3968 character of the string.
3969 If +'charIndex'+ is less than 0 or greater than
3970 or equal to the length of the string then an empty string is
3973 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'charIndex'+.
3975 +*string is* 'class' ?*-strict*? 'string'+::
3976 Returns 1 if +'string'+ is a valid member of the specified character
3977 class, otherwise returns 0. If +-strict+ is specified, then an
3978 empty string returns 0, otherwise an empty string will return 1
3979 on any class. The following character classes are recognized
3980 (the class name can be abbreviated):
3982 +alnum+;; Any alphabet or digit character.
3983 +alpha+;; Any alphabet character.
3984 +ascii+;; Any character with a value less than 128 (those that are in the 7-bit ascii range).
3985 +boolean+;; Any of the valid string formats for a boolean value in Tcl (0, false, no, off, 1, true, yes, on)
3986 +control+;; Any control character.
3987 +digit+;; Any digit character.
3988 +double+;; Any of the valid forms for a double in Tcl, with optional surrounding whitespace.
3989 In case of under/overflow in the value, 0 is returned.
3990 +graph+;; Any printing character, except space.
3991 +integer+;; Any of the valid string formats for an integer value in Tcl, with optional surrounding whitespace.
3992 +lower+;; Any lower case alphabet character.
3993 +print+;; Any printing character, including space.
3994 +punct+;; Any punctuation character.
3995 +space+;; Any space character.
3996 +upper+;; Any upper case alphabet character.
3997 +xdigit+;; Any hexadecimal digit character ([0-9A-Fa-f]).
3999 Note that string classification does +'not'+ respect UTF-8. See UTF-8 AND UNICODE
4001 Note that only +'lowercase'+ boolean values are recognized (Tcl accepts any case).
4003 +*string last* 'string1 string2 ?lastIndex?'+::
4004 Search +'string2'+ for a sequence of characters that exactly match
4005 the characters in +'string1'+. If found, return the index of the
4006 first character in the last such match within +'string2'+. If there
4007 is no match, then return -1. If +'lastIndex'+ is specified, only characters
4008 up to +'lastIndex'+ of +'string2'+ will be considered in the match.
4010 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'lastIndex'+.
4012 +*string length* 'string'+::
4013 Returns a decimal string giving the number of characters in +'string'+.
4014 If UTF-8 support is enabled, this may be different than the number of bytes.
4015 See UTF-8 AND UNICODE
4017 +*string map ?-nocase?* 'mapping string'+::
4018 Replaces substrings in +'string'+ based on the key-value pairs in
4019 +'mapping'+, which is a list of +key value key value \...+ as in the form
4020 returned by `array get`. Each instance of a key in the string will be
4021 replaced with its corresponding value. If +-nocase+ is specified, then
4022 matching is done without regard to case differences. Both key and value may
4023 be multiple characters. Replacement is done in an ordered manner, so the
4024 key appearing first in the list will be checked first, and so on. +'string'+ is
4025 only iterated over once, so earlier key replacements will have no affect for
4026 later key matches. For example,
4028 string map {abc 1 ab 2 a 3 1 0} 1abcaababcabababc
4031 will return the string +01321221+.
4033 Note that if an earlier key is a prefix of a later one, it will completely mask the later
4034 one. So if the previous example is reordered like this,
4036 string map {1 0 ab 2 a 3 abc 1} 1abcaababcabababc
4039 it will return the string +02c322c222c+.
4041 +*string match ?-nocase?* 'pattern string'+::
4042 See if +'pattern'+ matches +'string'+; return 1 if it does, 0
4043 if it doesn't. Matching is done in a fashion similar to that
4044 used by the C-shell. For the two strings to match, their contents
4045 must be identical except that the following special sequences
4046 may appear in +'pattern'+:
4049 Matches any sequence of characters in +'string'+,
4050 including a null string.
4053 Matches any single character in +'string'+.
4056 Matches any character in the set given by +'chars'+.
4057 If a sequence of the form +'x-y'+ appears in +'chars'+,
4058 then any character between +'x'+ and +'y'+, inclusive,
4062 Matches the single character +'x'+. This provides a way of
4063 avoiding the special interpretation of the characters +{backslash}*?[]+
4066 Performs a case-insensitive comparison if +-nocase+ is specified.
4068 +*string range* 'string first last'+::
4069 Returns a range of consecutive characters from +'string'+, starting
4070 with the character whose index is +'first'+ and ending with the
4071 character whose index is +'last'+. An index of 0 refers to the
4072 first character of the string.
4074 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
4076 If +'first'+ is less than zero then it is treated as if it were zero, and
4077 if +'last'+ is greater than or equal to the length of the string then
4078 it is treated as if it were +end+. If +'first'+ is greater than
4079 +'last'+ then an empty string is returned.
4081 +*string repeat* 'string count'+::
4082 Returns a new string consisting of +'string'+ repeated +'count'+ times.
4084 +*string replace* 'string first last ?newstring?'+::
4085 Removes a range of consecutive characters from +'string'+, starting
4086 with the character whose index is +'first'+ and ending with the
4087 character whose index is +'last'+. If +'newstring'+ is specified,
4088 then it is placed in the removed character range. If +'first'+ is
4089 less than zero then it is treated as if it were zero, and if +'last'+
4090 is greater than or equal to the length of the string then it is
4091 treated as if it were +end+. If +'first'+ is greater than +'last'+
4092 or the length of the initial string, or +'last'+ is less than 0,
4093 then the initial string is returned untouched.
4095 +*string reverse* 'string'+::
4096 Returns a string that is the same length as +'string'+ but
4097 with its characters in the reverse order.
4099 +*string tolower* 'string'+::
4100 Returns a value equal to +'string'+ except that all upper case
4101 letters have been converted to lower case.
4103 +*string totitle* 'string'+::
4104 Returns a value equal to +'string'+ except that the first character
4105 is converted to title case (or upper case if there is no UTF-8 titlecase variant)
4106 and all remaining characters have been converted to lower case.
4108 +*string toupper* 'string'+::
4109 Returns a value equal to +'string'+ except that all lower case
4110 letters have been converted to upper case.
4112 +*string trim* 'string ?chars?'+::
4113 Returns a value equal to +'string'+ except that any leading
4114 or trailing characters from the set given by +'chars'+ are
4116 If +'chars'+ is not specified then white space is removed
4117 (spaces, tabs, newlines, and carriage returns).
4119 +*string trimleft* 'string ?chars?'+::
4120 Returns a value equal to +'string'+ except that any
4121 leading characters from the set given by +'chars'+ are
4123 If +'chars'+ is not specified then white space is removed
4124 (spaces, tabs, newlines, and carriage returns).
4126 +*string trimright* 'string ?chars?'+::
4127 Returns a value equal to +'string'+ except that any
4128 trailing characters from the set given by +'chars'+ are
4130 If +'chars'+ is not specified then white space is removed
4131 (spaces, tabs, newlines, and carriage returns).
4132 Null characters are always removed.
4136 +*subst ?-nobackslashes? ?-nocommands? ?-novariables?* 'string'+
4138 This command performs variable substitutions, command substitutions,
4139 and backslash substitutions on its string argument and returns the
4140 fully-substituted result. The substitutions are performed in exactly
4141 the same way as for Tcl commands. As a result, the string argument
4142 is actually substituted twice, once by the Tcl parser in the usual
4143 fashion for Tcl commands, and again by the subst command.
4145 If any of the +-nobackslashes+, +-nocommands+, or +-novariables+ are
4146 specified, then the corresponding substitutions are not performed.
4147 For example, if +-nocommands+ is specified, no command substitution
4148 is performed: open and close brackets are treated as ordinary
4149 characters with no special interpretation.
4151 *Note*: when it performs its substitutions, subst does not give any
4152 special treatment to double quotes or curly braces. For example,
4153 the following script returns +xyz \{44\}+, not +xyz \{$a\}+.
4161 +*switch* '?options? string pattern body ?pattern body \...?'+
4163 +*switch* '?options? string {pattern body ?pattern body \...?}'+
4165 The `switch` command matches its string argument against each of
4166 the pattern arguments in order. As soon as it finds a pattern that
4167 matches string it evaluates the following body and returns the
4168 result of that evaluation. If the last pattern argument is default
4169 then it matches anything. If no pattern argument matches string and
4170 no default is given, then the `switch` command returns an empty string.
4171 If the initial arguments to switch start with - then they are treated
4172 as options. The following options are currently supported:
4175 Use exact matching when comparing string to a
4176 pattern. This is the default.
4179 When matching string to the patterns, use glob-style
4180 matching (i.e. the same as implemented by the string
4184 When matching string to the patterns, use regular
4185 expression matching (i.e. the same as implemented
4186 by the regexp command).
4188 +-command 'commandname'+::
4189 When matching string to the patterns, use the given command, which
4190 must be a single word. The command is invoked as
4191 'commandname pattern string', or 'commandname -nocase pattern string'
4192 and must return 1 if matched, or 0 if not.
4195 Marks the end of options. The argument following
4196 this one will be treated as string even if it starts
4199 Two syntaxes are provided for the pattern and body arguments. The
4200 first uses a separate argument for each of the patterns and commands;
4201 this form is convenient if substitutions are desired on some of the
4202 patterns or commands. The second form places all of the patterns
4203 and commands together into a single argument; the argument must
4204 have proper list structure, with the elements of the list being the
4205 patterns and commands. The second form makes it easy to construct
4206 multi-line `switch` commands, since the braces around the whole list
4207 make it unnecessary to include a backslash at the end of each line.
4208 Since the pattern arguments are in braces in the second form, no
4209 command or variable substitutions are performed on them; this makes
4210 the behaviour of the second form different than the first form in
4213 If a body is specified as +-+ it means that the body for the next
4214 pattern should also be used as the body for this pattern (if the
4215 next pattern also has a body of +-+ then the body after that is
4216 used, and so on). This feature makes it possible to share a single
4217 body among several patterns.
4219 Below are some examples of `switch` commands:
4221 switch abc a - b {format 1} abc {format 2} default {format 3}
4225 switch -regexp aaab {
4245 +*tailcall* 'cmd ?arg\...?'+
4247 The `tailcall` command provides an optimised way of invoking a command whilst replacing
4248 the current call frame. This is similar to 'exec' in Bourne Shell.
4250 The following are identical except the first immediately replaces the current call frame.
4254 return [uplevel 1 [list a b c]]
4256 `tailcall` is useful as a dispatch mechanism:
4259 tailcall sub_$cmd {*}$args
4270 Returns a decimal string giving the current access position in
4273 +'fileId'+ must have been the return value from a previous call to
4274 `open`, or it may be +stdin+, +stdout+, or +stderr+ to refer to one
4275 of the standard I/O channels.
4279 +*throw* 'code ?msg?'+
4281 This command throws an exception (return) code along with an optional message.
4282 This command is mostly for convenient usage with `try`.
4284 The command +throw break+ is equivalent to +break+.
4285 The command +throw 20 message+ can be caught with an +on 20 \...+ clause to `try`.
4289 +*time* 'command ?count?'+
4291 This command will call the Tcl interpreter +'count'+
4292 times to execute +'command'+ (or once if +'count'+ isn't
4293 specified). It will then return a string of the form
4295 503 microseconds per iteration
4297 which indicates the average amount of time required per iteration,
4300 Time is measured in elapsed time, not CPU time.
4304 +*try* '?catchopts? tryscript' ?*on* 'returncodes {?resultvar? ?optsvar?} handlerscript \...'? ?*finally* 'finalscript'?+
4306 The `try` command is provided as a convenience for exception handling.
4308 This interpeter first evaluates +'tryscript'+ under the effect of the catch
4309 options +'catchopts'+ (e.g. +-signal -noexit --+, see `catch`).
4311 It then evaluates the script for the first matching 'on' handler
4312 (there many be zero or more) based on the return code from the `try`
4313 section. For example a normal +JIM_ERR+ error will be matched by
4314 an 'on error' handler.
4316 Finally, any +'finalscript'+ is evaluated.
4318 The result of this command is the result of +'tryscript'+, except in the
4319 case where an exception occurs in a matching 'on' handler script or the 'finally' script,
4320 in which case the result is this new exception.
4322 The specified +'returncodes'+ is a list of return codes either as names ('ok', 'error', 'break', etc.)
4325 If +'resultvar'+ and +'optsvar'+ are specified, they are set as for `catch` before evaluating
4326 the matching handler.
4333 } on {continue break} {} {
4334 error "Unexpected break/continue"
4335 } on error {msg opts} {
4336 puts "Dealing with error"
4337 return {*}$opts $msg
4339 puts "Got signal: $sig"
4344 If break, continue or error are raised, they are dealt with by the matching
4347 In any case, the file will be closed via the 'finally' clause.
4349 See also `throw`, `catch`, `return`, `error`.
4353 +*unknown* 'cmdName ?arg arg ...?'+
4355 This command doesn't actually exist as part of Tcl, but Tcl will
4356 invoke it if it does exist.
4358 If the Tcl interpreter encounters a command name for which there
4359 is not a defined command, then Tcl checks for the existence of
4360 a command named `unknown`.
4362 If there is no such command, then the interpreter returns an
4365 If the `unknown` command exists, then it is invoked with
4366 arguments consisting of the fully-substituted name and arguments
4367 for the original non-existent command.
4369 The `unknown` command typically does things like searching
4370 through library directories for a command procedure with the name
4371 +'cmdName'+, or expanding abbreviated command names to full-length,
4372 or automatically executing unknown commands as UNIX sub-processes.
4374 In some cases (such as expanding abbreviations) `unknown` will
4375 change the original command slightly and then (re-)execute it.
4376 The result of the `unknown` command is used as the result for
4377 the original non-existent command.
4381 +*unset ?-nocomplain? ?--?* '?name name ...?'+
4384 Each +'name'+ is a variable name, specified in any of the
4385 ways acceptable to the `set` command.
4387 If a +'name'+ refers to an element of an array, then that
4388 element is removed without affecting the rest of the array.
4390 If a +'name'+ consists of an array name with no parenthesized
4391 index, then the entire array is deleted.
4393 The `unset` command returns an empty string as result.
4395 An error occurs if any of the variables doesn't exist, unless '-nocomplain'
4396 is specified. The '--' argument may be specified to stop option processing
4397 in case the variable name may be '-nocomplain'.
4401 +*upcall* 'command ?args ...?'+
4403 May be used from within a proc defined as `local` `proc` in order to call
4404 the previous, hidden version of the same command.
4406 If there is no previous definition of the command, an error is returned.
4410 +*uplevel* '?level? command ?command ...?'+
4412 All of the +'command'+ arguments are concatenated as if they had
4413 been passed to `concat`; the result is then evaluated in the
4414 variable context indicated by +'level'+. `uplevel` returns
4415 the result of that evaluation. If +'level'+ is an integer, then
4416 it gives a distance (up the procedure calling stack) to move before
4417 executing the command. If +'level'+ consists of +\#+ followed by
4418 a number then the number gives an absolute level number. If +'level'+
4419 is omitted then it defaults to +1+. +'level'+ cannot be
4420 defaulted if the first +'command'+ argument starts with a digit or +#+.
4422 For example, suppose that procedure 'a' was invoked
4423 from top-level, and that it called 'b', and that 'b' called 'c'.
4424 Suppose that 'c' invokes the `uplevel` command. If +'level'+
4425 is +1+ or +#2+ or omitted, then the command will be executed
4426 in the variable context of 'b'. If +'level'+ is +2+ or +#1+
4427 then the command will be executed in the variable context of 'a'.
4429 If +'level'+ is '3' or +#0+ then the command will be executed
4430 at top-level (only global variables will be visible).
4431 The `uplevel` command causes the invoking procedure to disappear
4432 from the procedure calling stack while the command is being executed.
4433 In the above example, suppose 'c' invokes the command
4435 uplevel 1 {set x 43; d}
4437 where 'd' is another Tcl procedure. The `set` command will
4438 modify the variable 'x' in 'b's context, and 'd' will execute
4439 at level 3, as if called from 'b'. If it in turn executes
4444 then the `set` command will modify the same variable 'x' in 'b's
4445 context: the procedure 'c' does not appear to be on the call stack
4446 when 'd' is executing. The command `info level` may
4447 be used to obtain the level of the current procedure.
4449 `uplevel` makes it possible to implement new control
4450 constructs as Tcl procedures (for example, `uplevel` could
4451 be used to implement the `while` construct as a Tcl procedure).
4455 +*upvar* '?level? otherVar myVar ?otherVar myVar ...?'+
4457 This command arranges for one or more local variables in the current
4458 procedure to refer to variables in an enclosing procedure call or
4459 to global variables.
4461 +'level'+ may have any of the forms permitted for the `uplevel`
4462 command, and may be omitted if the first letter of the first +'otherVar'+
4463 isn't +#+ or a digit (it defaults to '1').
4465 For each +'otherVar'+ argument, `upvar` makes the variable
4466 by that name in the procedure frame given by +'level'+ (or at
4467 global level, if +'level'+ is +#0+) accessible
4468 in the current procedure by the name given in the corresponding
4471 The variable named by +'otherVar'+ need not exist at the time of the
4472 call; it will be created the first time +'myVar'+ is referenced, just like
4473 an ordinary variable.
4475 `upvar` may only be invoked from within procedures.
4477 `upvar` returns an empty string.
4479 The `upvar` command simplifies the implementation of call-by-name
4480 procedure calling and also makes it easier to build new control constructs
4482 For example, consider the following procedure:
4489 'add2' is invoked with an argument giving the name of a variable,
4490 and it adds two to the value of that variable.
4491 Although 'add2' could have been implemented using `uplevel`
4492 instead of `upvar`, `upvar` makes it simpler for 'add2'
4493 to access the variable in the caller's procedure frame.
4499 +*wait -nohang* 'pid'+
4501 With no arguments, cleans up any processes started by `exec ... &` that have completed
4502 (reaps zombie processes).
4504 With one or two arguments, waits for a process by id, either returned by `exec ... &`
4505 or by `os.fork` (if supported).
4507 Waits for the process to complete, unless +-nohang+ is specified, in which case returns
4508 immediately if the process is still running.
4510 Returns a list of 3 elements.
4512 +{NONE x x}+ if the process does not exist or has already been waited for, or
4513 if -nohang is specified, and the process is still alive.
4515 +{CHILDSTATUS <pid> <exit-status>}+ if the process exited normally.
4517 +{CHILDKILLED <pid> <signal>}+ if the process terminated on a signal.
4519 +{CHILDSUSP <pid> none}+ if the process terminated for some other reason.
4521 Note that on platforms supporting waitpid(2), +pid+ can also be given special values such
4522 as 0 or -1. See waitpid(2) for more detail.
4526 +*while* 'test body'+
4528 The +'while'+ command evaluates +'test'+ as an expression
4529 (in the same way that `expr` evaluates its argument).
4530 The value of the expression must be numeric; if it is non-zero
4531 then +'body'+ is executed by passing it to the Tcl interpreter.
4533 Once +'body'+ has been executed then +'test'+ is evaluated
4534 again, and the process repeats until eventually +'test'+
4535 evaluates to a zero numeric value. `continue`
4536 commands may be executed inside +'body'+ to terminate the current
4537 iteration of the loop, and `break`
4538 commands may be executed inside +'body'+ to cause immediate
4539 termination of the `while` command.
4541 The `while` command always returns an empty string.
4546 The following extensions may or may not be available depending upon
4547 what options were selected when Jim Tcl was built.
4551 posix: os.fork, os.gethostname, os.getids, os.uptime
4552 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4554 Invokes 'fork(2)' and returns the result.
4556 +*os.gethostname*+::
4557 Invokes 'gethostname(3)' and returns the result.
4560 Returns the various user/group ids for the current process.
4563 uid 1000 euid 1000 gid 100 egid 100
4566 Returns the number of seconds since system boot. See description of 'uptime' in 'sysinfo(2)'.
4568 ANSI I/O (aio) and EVENTLOOP API
4569 --------------------------------
4570 Jim provides an alternative object-based API for I/O.
4572 See `open` and `socket` for commands which return an I/O handle.
4576 +$handle *accept* ?addrvar?+::
4577 Server socket only: Accept a connection and return stream.
4578 If +'addrvar'+ is specified, the address of the connected client is stored
4579 in the named variable in the form 'addr:port' for IP sockets or 'path' for Unix domain sockets.
4580 See `socket` for details.
4582 +$handle *buffering none|line|full*+::
4583 Sets the buffering mode of the stream.
4585 +$handle *close ?r(ead)|w(rite)|-nodelete?*+::
4587 The +'read'+ and +'write'+ arguments perform a "half-close" on a socket. See the 'shutdown(2)' man page.
4588 The +'-nodelete'+ option is applicable only for Unix domain sockets. It closes the socket
4589 but does not delete the bound path (e.g. after `os.fork`).
4592 +$handle *copyto* 'tofd ?size?'+::
4593 Copy bytes to the file descriptor +'tofd'+. If +'size'+ is specified, at most
4594 that many bytes will be copied. Otherwise copying continues until the end
4595 of the input file. Returns the number of bytes actually copied.
4598 Returns 1 if stream is at eof
4600 +$handle *filename*+::
4601 Returns the original filename associated with the handle.
4602 Handles returned by `socket` give the socket type instead of a filename.
4607 +$handle *gets* '?var?'+::
4608 Read one line and return it or store it in the var
4610 +$handle *isatty*+::
4611 Returns 1 if the stream is a tty device.
4613 +$handle *lock ?-wait?*+::
4614 Apply a POSIX lock to the open file associated with the handle using
4615 'fcntl(F_SETLK)', or 'fcntl(F_SETLKW)' to wait for the lock to be available if +'-wait'+
4617 The handle must be open for write access.
4618 Returns 1 if the lock was successfully obtained, 0 otherwise.
4619 An error occurs if the handle is not suitable for locking (e.g.
4620 if it is not open for write)
4622 +$handle *ndelay ?0|1?*+::
4623 Set O_NDELAY (if arg). Returns current/new setting.
4624 Note that in general ANSI I/O interacts badly with non-blocking I/O.
4627 +$handle *peername*+::
4628 Returns the remote address or path of the connected socket. See 'getpeername(2)'.
4630 +$handle *puts ?-nonewline?* 'str'+::
4631 Write the string, with newline unless -nonewline
4633 +$handle *read ?-nonewline?* '?len?'+::
4634 Read and return bytes from the stream. To eof if no len.
4636 +$handle *recvfrom* 'maxlen ?addrvar?'+::
4637 Receives a message from the handle via recvfrom(2) and returns it.
4638 At most +'maxlen'+ bytes are read. If +'addrvar'+ is specified, the sending address
4639 of the message is stored in the named variable in the form 'addr:port' for IP sockets
4640 or 'path' for Unix domain sockets. See `socket` for details.
4642 +$handle *seek* 'offset' *?start|current|end?*+::
4643 Seeks in the stream (default 'current')
4645 +$handle *sendto* 'str ?address'+::
4646 Sends the string, +'str'+, to the given address (host:port or path) via the socket using 'sendto(2)'.
4647 This is intended for udp/dgram sockets and may give an error or behave in unintended
4648 ways for other handle types.
4649 Returns the number of bytes written.
4651 +$handle *sockname*+::
4652 Returns the bound address or path of the socket. See 'getsockname(2)'.
4654 +$handle *sockopt* '?name value?'+::
4655 With no arguments, returns a dictionary of socket options currently set for the handle
4656 (will be empty for a non-socket). With +'name'+ and +'value'+, sets the socket option
4657 to the given value. Currently supports the following boolean socket options:
4658 +broadcast, debug, keepalive, nosigpipe, oobinline, tcp_nodelay+, and the following
4659 integer socket options: +sndbuf, rcvbuf+
4662 Flush the stream, then 'fsync(2)' to commit any changes to storage.
4663 Only available on platforms that support 'fsync(2)'.
4666 Returns the current seek position
4668 +$handle *tty* ?settings?+::
4669 If no arguments are given, returns a dictionary containing the tty settings for the stream.
4670 If arguments are given, they must either be a dictionary, or +setting value \...+
4671 Abbrevations are supported for both settings and values, so the following is acceptable:
4672 +$f tty parity e input c out raw+.
4673 Only available on platforms that support 'termios(3)'. Supported settings are:
4676 Baud rate. e.g. 115200
4684 +*parity even|odd|none*+;;
4687 +*handshake xonxoff|rtscts|none*+;;
4690 +*input raw|cooked*+;;
4691 Input character processing. In raw mode, the usual key sequences such as ^C do
4692 not generate signals.
4694 +*output raw|cooked*+;;
4695 Output character processing. Typically CR -> CRNL is disabled in raw mode.
4697 +*vmin* 'numchars'+;;
4698 Minimum number of characters to read.
4701 Timeout for noncanonical read (units of 0.1 seconds)
4703 +$handle *ssl* ?*-server* 'cert priv'?+::
4704 Upgrades the stream to a SSL/TLS session and returns the handle.
4706 +$handle *unlock*+::
4707 Release a POSIX lock previously acquired by `aio lock`.
4709 +$handle *verify*+::
4710 Verifies the certificate of a SSL/TLS stream peer
4712 +*load_ssl_certs* 'dir'+::
4713 Loads SSL/TLS CA certificates for use during verification
4717 +*fconfigure* 'handle' *?-blocking 0|1? ?-buffering noneline|full? ?-translation* 'mode'?+::
4718 For compatibility with Tcl, a limited form of the `fconfigure`
4719 command is supported.
4720 * `fconfigure ... -blocking` maps to `aio ndelay`
4721 * `fconfigure ... -buffering` maps to `aio buffering`
4722 * `fconfigure ... -translation` is accepted but ignored
4725 eventloop: after, vwait, update
4726 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4728 The following commands allow a script to be invoked when the given condition occurs.
4729 If no script is given, returns the current script. If the given script is the empty, the
4732 +$handle *readable* '?readable-script?'+::
4733 Sets or returns the script for when the socket is readable.
4735 +$handle *writable* '?writable-script?'+::
4736 Sets or returns the script for when the socket is writable.
4738 +$handle *onexception* '?exception-script?'+::
4739 Sets or returns the script for when oob data received.
4741 For compatibility with 'Tcl', these may be prefixed with `fileevent`. e.g.
4744 +fileevent $handle *readable* '\...'+
4746 Time-based execution is also available via the eventloop API.
4749 Sleeps for the given number of milliseconds. No events are
4750 processed during this time.
4752 +*after* 'ms'|*idle* 'script ?script \...?'+::
4753 The scripts are concatenated and executed after the given
4754 number of milliseconds have elapsed. If 'idle' is specified,
4755 the script will run the next time the event loop is processed
4756 with `vwait` or `update`. The script is only run once and
4757 then removed. Returns an event id.
4759 +*after cancel* 'id|command'+::
4760 Cancels an `after` event with the given event id or matching
4761 command (script). Returns the number of milliseconds
4762 remaining until the event would have fired. Returns the
4763 empty string if no matching event is found.
4765 +*after info* '?id?'+::
4766 If +'id'+ is not given, returns a list of current `after`
4767 events. If +'id'+ is given, returns a list containing the
4768 associated script and either 'timer' or 'idle' to indicated
4769 the type of the event. An error occurs if +'id'+ does not
4772 +*vwait* 'variable'+::
4773 A call to `vwait` enters the eventloop. `vwait` processes
4774 events until the named (global) variable changes or all
4775 event handlers are removed. The variable need not exist
4776 beforehand. If there are no event handlers defined, `vwait`
4777 returns immediately.
4779 +*update ?idletasks?*+::
4780 A call to `update` enters the eventloop to process expired events, but
4781 no new events. If 'idletasks' is specified, only expired time events are handled,
4783 Returns once handlers have been run for all expired events.
4785 Scripts are executed at the global scope. If an error occurs during a handler script,
4786 an attempt is made to call (the user-defined command) `bgerror` with the details of the error.
4787 If the `bgerror` command does not exist, the error message details are printed to stderr instead.
4789 If a file event handler script generates an error, the handler is automatically removed
4790 to prevent infinite errors. (A time event handler is always removed after execution).
4793 Called when an event handler script generates an error. Note that the normal command resolution
4794 rules are used for bgerror. First the name is resolved in the current namespace, then in the
4799 Various socket types may be created.
4801 +*socket unix* 'path'+::
4802 A unix domain socket client connected to 'path'
4804 +*socket unix.server* 'path'+::
4805 A unix domain socket server listening on 'path'
4807 +*socket unix.dgram* '?path?'+::
4808 A unix domain socket datagram client, optionally connected to 'path'
4810 +*socket unix.dgram.server* 'path'+::
4811 A unix domain socket datagram server server listening on 'path'
4813 +*socket ?-ipv6? stream* 'addr:port'+::
4814 A TCP socket client. (See the forms for +'addr'+ below)
4816 +*socket ?-ipv6? stream.server* '?addr:?port'+::
4817 A TCP socket server (+'addr'+ defaults to +0.0.0.0+ for IPv4 or +[::]+ for IPv6).
4819 +*socket ?-ipv6? dgram* ?'addr:port'?+::
4820 A UDP socket client. If the address is not specified,
4821 the client socket will be unbound and 'sendto' must be used
4822 to indicated the destination.
4824 +*socket ?-ipv6? dgram.server* 'addr:port'+::
4825 A UDP socket server.
4828 A synonym for `pipe`
4831 A socketpair (see socketpair(2)). Like `pipe`, this command returns
4832 a list of two channels: {s1 s2}. These channels are both readable and writable.
4834 This command creates a socket connected (client) or bound (server) to the given
4837 The returned value is channel and may generally be used with the various file I/O
4838 commands (gets, puts, read, etc.), either as object-based syntax or Tcl-compatible syntax.
4840 . set f [socket stream www.google.com:80]
4842 . $f puts -nonewline "GET / HTTP/1.0\r\n\r\n"
4847 Server sockets, however support only 'accept', which is most useful in conjunction with
4850 set f [socket stream.server 80]
4852 set client [$f accept]
4855 $client puts -nonewline "HTTP/1.1 404 Not found\r\n"
4860 The address, +'addr'+, can be given in one of the following forms:
4862 1. For IPv4 socket types, an IPv4 address such as 192.168.1.1
4863 2. For IPv6 socket types, an IPv6 address such as [fe80::1234] or [::]
4866 Note that on many systems, listening on an IPv6 address such as [::] will
4867 also accept requests via IPv4.
4869 Where a hostname is specified, the +'first'+ returned address is used
4870 which matches the socket type is used.
4872 An unconnected dgram socket (either 'dgram' or 'unix.dgram') must use
4873 `sendto` to specify the destination address.
4875 The path for Unix domain sockets is automatically removed when the socket
4876 is closed. Use `close -nodelete` in the rare case where this behaviour
4877 should be avoided (e.g. after `os.fork`).
4881 +*syslog* '?options? ?priority? message'+
4883 This command sends message to system syslog facility with given
4884 priority. Valid priorities are:
4886 emerg, alert, crit, err, error, warning, notice, info, debug
4888 If a message is specified, but no priority is specified, then a
4889 priority of info is used.
4891 By default, facility user is used and the value of global tcl variable
4892 argv0 is used as ident string. However, any of the following options
4893 may be specified before priority to control these parameters:
4895 +*-facility* 'value'+::
4896 Use specified facility instead of user. The following
4897 values for facility are recognized:
4899 authpriv, cron, daemon, kernel, lpr, mail, news, syslog, user,
4902 +*-ident* 'string'+::
4903 Use given string instead of argv0 variable for ident string.
4905 +*-options* 'integer'+::
4906 Set syslog options such as +LOG_CONS+, +LOG_NDELAY+. You should
4907 use numeric values of those from your system syslog.h file,
4908 because I haven't got time to implement yet another hash
4913 The optional 'pack' extension provides commands to encode and decode binary strings.
4915 +*pack* 'varName value' *-intle|-intbe|-floatle|-floatbe|-str* 'bitwidth ?bitoffset?'+::
4916 Packs the binary representation of +'value'+ into the variable
4917 +'varName'+. The value is packed according to the given type
4918 (integer/floating point/string, big-endian/little-endian), width and bit offset.
4919 The variable is created if necessary (like `append`).
4920 The variable is expanded if necessary.
4922 +*unpack* 'binvalue' *-intbe|-intle|-uintbe|-uintle|-floatbe|-floatle|-str* 'bitpos bitwidth'+::
4923 Unpacks bits from +'binvalue'+ at bit position +'bitpos'+ and with +'bitwidth'+.
4924 Interprets the value according to the type (integer/floating point/string, big-endian/little-endian
4925 and signed/unsigned) and returns it. For integer types, +'bitwidth'+
4926 may be up to the size of a Jim Tcl integer (typically 64 bits). For floating point types,
4927 +'bitwidth'+ may be 32 bits (for single precision numbers) or 64 bits (for double precision).
4928 For the string type, both the width and the offset must be on a byte boundary (multiple of 8). Attempting to
4929 access outside the length of the value will return 0 for integer types, 0.0 for floating point types
4930 or the empty string for the string type.
4934 The optional 'zlib' extension provides a Tcl-compatible subset of the `zlib` command.
4936 +*crc32* 'data' '?startValue?'+::
4937 Returns the CRC32 checksum of a buffer. Optionally, an initial value may be specified; this is most useful
4938 for calculating the checksum of chunked data read from a stream (for instance, a pipe).
4940 +*deflate* 'string' '?level?'+::
4941 Compresses a buffer and outputs a raw, Deflate-compressed stream. Optionally, a compression level (1-9) may
4942 be specified to choose the desired speed vs. compression rate ratio.
4944 +*inflate* 'data' '?bufferSize?'+::
4945 Decompresses a raw, Deflate-compressed stream. When the uncompressed data size is known and specified, memory
4946 allocation is more efficient. Otherwise, decomperssion is chunked and therefore slower.
4948 +*gzip* 'string' '?-level level?'+::
4949 Compresses a buffer and adds a gzip header.
4951 +*gunzip* 'data' '?-buffersize size?'+::
4952 Decompresses a gzip-compressed buffer. Decompression is chunked, with a default, small buffer size of 64K
4953 which guarantees lower memory footprint at the cost of speed. It is recommended to use a bigger size, on
4954 systems without a severe memory constraint.
4958 The optional, pure-Tcl 'binary' extension provides the Tcl-compatible `binary scan` and `binary format`
4959 commands based on the low-level `pack` and `unpack` commands.
4961 See the Tcl documentation at: http://www.tcl.tk/man/tcl8.5/TclCmd/binary.htm
4963 Note that 'binary format' with f/r/R specifiers (single-precision float) uses the value of Infinity
4964 in case of overflow.
4968 The optional, pure-Tcl 'oo' extension provides object-oriented (OO) support for Jim Tcl.
4970 See the online documentation (http://jim.tcl.tk/index.html/doc/www/www/documentation/oo/) for more details.
4972 +*class* 'classname ?baseclasses? classvars'+::
4973 Create a new class, +'classname'+, with the given dictionary
4974 (+'classvars'+) as class variables. These are the initial variables
4975 which all newly created objects of this class are initialised with.
4976 If a list of baseclasses is given, methods and instance variables
4979 +*super* 'method ?args \...?'+::
4980 From within a method, invokes the given method on the base class.
4981 Note that this will only call the last baseclass given.
4985 The optional, pure-Tcl 'tree' extension implements an OO, general purpose tree structure
4986 similar to that provided by tcllib ::struct::tree (http://core.tcl.tk/tcllib/doc/trunk/embedded/www/tcllib/files/modules/struct/struct_tree.html)
4988 A tree is a collection of nodes, where each node (except the root node) has a single parent
4989 and zero or more child nodes (ordered), as well as zero or more attribute/value pairs.
4992 Creates and returns a new tree object with a single node named "root".
4993 All operations on the tree are invoked through this object.
4996 Destroy the tree and all it's nodes. (Note that the tree will also
4997 be automatically garbage collected once it goes out of scope).
4999 +$tree *set* 'nodename key value'+::
5000 Set the value for the given attribute key.
5002 +$tree *lappend* 'nodename key value \...'+::
5003 Append to the (list) value(s) for the given attribute key, or set if not yet set.
5005 +$tree *keyexists* 'nodename key'+::
5006 Returns 1 if the given attribute key exists.
5008 +$tree *get* 'nodename key'+::
5009 Returns the value associated with the given attribute key.
5011 +$tree *getall* 'nodename'+::
5012 Returns the entire attribute dictionary associated with the given key.
5014 +$tree *depth* 'nodename'+::
5015 Returns the depth of the given node. The depth of "root" is 0.
5017 +$tree *parent* 'nodename'+::
5018 Returns the node name of the parent node, or "" for the root node.
5020 +$tree *numchildren* 'nodename'+::
5021 Returns the number of child nodes.
5023 +$tree *children* 'nodename'+::
5024 Returns a list of the child nodes.
5026 +$tree *next* 'nodename'+::
5027 Returns the next sibling node, or "" if none.
5029 +$tree *insert* 'nodename ?index?'+::
5030 Add a new child node to the given node. The index is a list index
5031 such as +3+ or +end-2+. The default index is +end+.
5032 Returns the name of the newly added node.
5034 +$tree *walk* 'nodename' *dfs|bfs* {'actionvar nodevar'} 'script'+::
5035 Walks the tree starting from the given node, either breadth first (+bfs+)
5036 depth first (+dfs+).
5037 The value +"enter"+ or +"exit"+ is stored in variable +'actionvar'+.
5038 The name of each node is stored in +'nodevar'+.
5039 The script is evaluated twice for each node, on entry and exit.
5042 Dumps the tree contents to stdout
5046 The optional tclprefix extension provides the Tcl8.6-compatible `tcl::prefix` command
5047 (http://www.tcl.tk/man/tcl8.6/TclCmd/prefix.htm) for matching strings against a table
5048 of possible values (typically commands or options).
5050 +*tcl::prefix all* 'table string'+::
5051 Returns a list of all elements in +'table'+ that begin with the prefix +'string'+.
5053 +*tcl::prefix longest* 'table string'+::
5054 Returns the longest common prefix of all elements in +'table'+ that begin with the prefix +'string'+.
5056 +*tcl::prefix match* '?options? table string'+::
5057 If +'string'+ equals one element in +'table'+ or is a prefix to
5058 exactly one element, the matched element is returned. If not, the
5059 result depends on the +-error+ option.
5061 * +*-exact*+ Accept only exact matches.
5062 * +*-message* 'string'+ Use +'string'+ in the error message at a mismatch. Default is "option".
5063 * +*-error* 'options'+ The options are used when no match is found. If +'options'+ is
5064 empty, no error is generated and an empty string is returned.
5065 Otherwise the options are used as return options when
5066 generating the error message. The default corresponds to
5071 Scriptable command line completion is supported in the interactive shell, 'jimsh', through
5072 the `tcl::autocomplete` callback. A simple implementation is provided, however this may
5073 be replaced with a custom command instead if desired.
5075 In the interactive shell, press <TAB> to activate command line completion.
5077 +*tcl::autocomplete* 'commandline'+::
5078 This command is called with the current command line when the user presses <TAB>.
5079 The command should return a list of all possible command lines that match the current command line.
5080 For example if +*pr*+ is the current command line, the list +*{prefix proc}*+ may be returned.
5084 The optional history extension provides script access to the command line editing
5085 and history support available in 'jimsh'. See 'examples/jtclsh.tcl' for an example.
5086 Note: if line editing support is not available, `history getline` acts like `gets` and
5087 the remaining subcommands do nothing.
5089 +*history load* 'filename'+::
5090 Load history from a (text) file. If the file does not exist or is not readable,
5093 +*history getline* 'prompt ?varname?'+::
5094 Displays the given prompt and allows a line to be entered. Similarly to `gets`,
5095 if +'varname'+ is given, it receives the line and the length of the line is returned,
5096 or -1 on EOF. If +'varname'+ is not given, the line is returned directly.
5098 +*history completion* 'command'+::
5099 Sets an autocompletion command (see `tcl::autocomplete`) that is active during `history getline`.
5100 If the command is empty, autocompletion is disabled.
5102 +*history add* 'line'+::
5103 Adds the given line to the history buffer.
5105 +*history save* 'filename'+::
5106 Saves the current history buffer to the given file.
5109 Displays the current history buffer to standard output.
5113 Provides namespace-related functions. See also: http://www.tcl.tk/man/tcl8.6/TclCmd/namespace.htm
5115 +*namespace code* 'script'+::
5116 Captures the current namespace context for later execution of
5117 the script +'script'+. It returns a new script in which script has
5118 been wrapped in a +*namespace inscope*+ command.
5120 +*namespace current*+::
5121 Returns the fully-qualified name for the current namespace.
5123 +*namespace delete* '?namespace ...?'+::
5124 Deletes all commands and variables with the given namespace prefixes.
5126 +*namespace eval* 'namespace arg ?arg...?'+::
5127 Activates a namespace called +'namespace'+ and evaluates some code in that context.
5129 +*namespace origin* 'command'+::
5130 Returns the fully-qualified name of the original command to which the imported command +'command'+ refers.
5132 +*namespace parent* ?namespace?+::
5133 Returns the fully-qualified name of the parent namespace for namespace +'namespace'+, if given, otherwise
5134 for the current namespace.
5136 +*namespace qualifiers* 'string'+::
5137 Returns any leading namespace qualifiers for +'string'+
5139 +*namespace tail* 'string'+::
5140 Returns the simple name at the end of a qualified string.
5142 +*namespace upvar* 'namespace ?arg...?'+::
5143 This command arranges for zero or more local variables in the current procedure to refer to variables in +'namespace'+
5145 +*namespace which* '?-command|-variable? name'+::
5146 Looks up +'name'+ as either a command (the default) or variable and returns its fully-qualified name.
5150 The optional 'interp' command allows sub-interpreters to be created where commands may be run
5151 independently (but synchronously) of the main interpreter.
5154 Creates and returns a new interpreter object (command).
5155 The created interpeter contains any built-in commands along with static extensions,
5156 but does not include any dynamically loaded commands (package require, load).
5157 These must be reloaded in the child interpreter if required.
5159 +*$interp delete*+::
5160 Deletes the interpeter object.
5162 +*$interp eval* 'script' ...+::
5163 Evaluates a script in the context for the child interpreter, in the same way as 'eval'.
5165 +*$interp alias* 'alias childcmd parentcmd ?arg ...?'+::
5166 Similar to 'alias', but creates a command, +'childcmd'+, in the child interpreter that is an
5167 alias for +'parentcmd'+ in the parent interpreter, with the given, fixed arguments.
5168 The alias may be deleted in the child with 'rename'.
5170 [[BuiltinVariables]]
5174 The following global variables are created automatically
5178 This variable is set by Jim as an array
5179 whose elements are the environment variables for the process.
5180 Reading an element will return the value of the corresponding
5181 environment variable.
5182 This array is initialised at startup from the `env` command.
5183 It may be modified and will affect the environment passed to
5184 commands invoked with `exec`.
5187 This variable is set by Jim as an array containing information
5188 about the platform on which Jim was built. Currently this includes
5189 'os' and 'platform'.
5192 This variable contains a list of paths to search for packages.
5193 It defaults to a location based on where jim is installed
5194 (e.g. +/usr/local/lib/jim+), but may be changed by +jimsh+
5195 or the embedding application. Note that +jimsh+ will consider
5196 the environment variable +$JIMLIB+ to be a list of colon-separated
5197 list of paths to add to +*auto_path*+.
5200 This variable holds the value of the -errorcode return
5201 option set by the most recent error that occurred in this
5202 interpreter. This list value represents additional information
5203 about the error in a form that is easy to process with
5204 programs. The first element of the list identifies a general
5205 class of errors, and determines the format of the rest of
5206 the list. The following formats for -errorcode return options
5207 are used by the Tcl core; individual applications may define
5208 additional formats. Currently only `exec` sets this variable.
5209 Otherwise it will be +NONE+.
5211 The following global variables are set by jimsh.
5213 +*tcl_interactive*+::
5214 This variable is set to 1 if jimsh is started in interactive mode
5218 This variable is set by Jim as an array containing information
5219 about the platform upon which Jim was built. The following is an
5220 example of the contents of this array.
5222 tcl_platform(byteOrder) = littleEndian
5223 tcl_platform(engine) = Jim
5224 tcl_platform(os) = Darwin
5225 tcl_platform(platform) = unix
5226 tcl_platform(pointerSize) = 8
5227 tcl_platform(threaded) = 0
5228 tcl_platform(wordSize) = 8
5229 tcl_platform(pathSeparator) = :
5232 If jimsh is invoked to run a script, this variable contains the name
5236 If jimsh is invoked to run a script, this variable contains a list
5237 of any arguments supplied to the script.
5240 If jimsh is invoked to run a script, this variable contains the number
5241 of arguments supplied to the script.
5244 The value of argv[0] when jimsh was invoked.
5246 The following variables have special meaning to Jim Tcl:
5249 If this variable is set, it is considered to be a list of scripts to evaluate
5250 when the current proc exits (local variables), or the interpreter exits (global variable).
5253 +*history::multiline*+::
5254 If this variable is set to "1", interactive line editing operates in multiline mode.
5255 That is, long lines will wrap across multiple lines rather than scrolling within a
5258 CHANGES IN PREVIOUS RELEASES
5259 ----------------------------
5263 1. +platform_tcl()+ settings are now automatically determined
5264 2. Add aio `$handle filename`
5265 3. Add `info channels`
5266 4. The 'bio' extension is gone. Now `aio` supports 'copyto'.
5267 5. Add `exists` command
5268 6. Add the pure-Tcl 'oo' extension
5269 7. The `exec` command now only uses vfork(), not fork()
5270 8. Unit test framework is less verbose and more Tcl-compatible
5271 9. Optional UTF-8 support
5272 10. Optional built-in regexp engine for better Tcl compatibility and UTF-8 support
5273 11. Command line editing in interactive mode, e.g. 'jimsh'
5277 1. `source` now checks that a script is complete (.i.e. not missing a brace)
5278 2. 'info complete' now uses the real parser and so is 100% accurate
5279 3. Better access to live stack frames with 'info frame', `stacktrace` and `stackdump`
5280 4. `tailcall` no longer loses stack trace information
5281 5. Add `alias` and `curry`
5282 6. `lambda`, `alias` and `curry` are implemented via `tailcall` for efficiency
5283 7. `local` allows procedures to be deleted automatically at the end of the current procedure
5284 8. udp sockets are now supported for both clients and servers.
5285 9. vfork-based exec is now working correctly
5286 10. Add 'file tempfile'
5287 11. Add 'socket pipe'
5288 12. Enhance 'try ... on ... finally' to be more Tcl 8.6 compatible
5289 13. It is now possible to `return` from within `try`
5290 14. IPv6 support is now included
5292 16. Event handlers works better if an error occurs. eof handler has been removed.
5293 17. `exec` now sets $::errorCode, and catch sets opts(-errorcode) for exit status
5294 18. Command pipelines via open "|..." are now supported
5295 19. `pid` can now return pids of a command pipeline
5296 20. Add 'info references'
5297 21. Add support for 'after +'ms'+', 'after idle', 'after info', `update`
5298 22. `exec` now sets environment based on $::env
5300 24. Add support for 'lsort -index'
5304 1. Add support to `exec` for '>&', '>>&', '|&', '2>@1'
5305 2. Fix `exec` error messages when special token (e.g. '>') is the last token
5306 3. Fix `subst` handling of backslash escapes.
5307 4. Allow abbreviated options for `subst`
5308 5. Add support for `return`, `break`, `continue` in subst
5309 6. Many `expr` bug fixes
5310 7. Add support for functions in `expr` (e.g. int(), abs()), and also 'in', 'ni' list operations
5311 8. The variable name argument to `regsub` is now optional
5312 9. Add support for 'unset -nocomplain'
5313 10. Add support for list commands: `lassign`, `lrepeat`
5314 11. Fully-functional `lsearch` is now implemented
5315 12. Add 'info nameofexecutable' and 'info returncodes'
5316 13. Allow `catch` to determine what return codes are caught
5317 14. Allow `incr` to increment an unset variable by first setting to 0
5318 15. Allow 'args' and optional arguments to the left or required arguments in `proc`
5320 17. Add 'try ... finally' command
5326 Copyright 2005 Salvatore Sanfilippo <antirez@invece.org>
5327 Copyright 2005 Clemens Hintze <c.hintze@gmx.net>
5328 Copyright 2005 patthoyts - Pat Thoyts <patthoyts@users.sf.net>
5329 Copyright 2008 oharboe - Oyvind Harboe - oyvind.harboe@zylin.com
5330 Copyright 2008 Andrew Lunn <andrew@lunn.ch>
5331 Copyright 2008 Duane Ellis <openocd@duaneellis.com>
5332 Copyright 2008 Uwe Klein <uklein@klein-messgeraete.de>
5333 Copyright 2009 Steve Bennett <steveb@workware.net.au>
5336 Redistribution and use in source and binary forms, with or without
5337 modification, are permitted provided that the following conditions
5339 1. Redistributions of source code must retain the above copyright
5340 notice, this list of conditions and the following disclaimer.
5341 2. Redistributions in binary form must reproduce the above
5342 copyright notice, this list of conditions and the following
5343 disclaimer in the documentation and/or other materials
5344 provided with the distribution.
5346 THIS SOFTWARE IS PROVIDED BY THE JIM TCL PROJECT ``AS IS'' AND ANY
5347 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
5348 THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
5349 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
5350 JIM TCL PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
5351 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
5352 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
5353 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
5354 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
5355 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
5356 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
5357 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
5359 The views and conclusions contained in the software and documentation
5360 are those of the authors and should not be interpreted as representing
5361 official policies, either expressed or implied, of the Jim Tcl Project.