6 Jim Tcl v0.76+ - reference manual for the Jim Tcl scripting language
16 jimsh -e '<immediate-script>'
21 * <<CommandIndex,Command Reference>>
22 * <<OperatorPrecedence,Operator Precedence>>
23 * <<BuiltinVariables, Builtin Variables>>
24 * <<BackslashSequences, Backslash Sequences>>
28 Jim Tcl is a small footprint reimplementation of the Tcl scripting language.
29 The core language engine is compatible with Tcl 8.5+, while implementing
30 a significant subset of the Tcl 8.6 command set, plus additional features
31 available only in Jim Tcl.
33 Some notable differences with Tcl 8.5/8.6 are:
35 1. Object-based I/O (aio), but with a Tcl-compatibility layer
36 2. I/O: Support for sockets and pipes including udp, unix domain sockets and IPv6
38 4. Support for references (`ref`/`getref`/`setref`) and garbage collection
39 5. Builtin dictionary type (`dict`) with some limitations compared to Tcl 8.6
40 6. `env` command to access environment variables
41 7. Operating system features: `os.fork`, `os.wait`, `os.uptime`, `signal`, `alarm`, `sleep`
42 8. Much better error reporting. `info stacktrace` as a replacement for '$errorInfo', '$errorCode'
43 9. Support for "static" variables in procedures
44 10. Threads and coroutines are not supported
45 11. Command and variable traces are not supported
46 12. Built-in command line editing
47 13. Expression shorthand syntax: +$(...)+
48 14. Modular build allows many features to be omitted or built as dynamic, loadable modules
49 15. Highly suitable for use in an embedded environment
50 16. Support for UDP, IPv6, Unix-Domain sockets in addition to TCP sockets
54 Changes between 0.76 and 0.77
55 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
56 1. Add support for `aio sync`
57 2. Add SSL and TLS support in aio
60 Changes between 0.75 and 0.76
61 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
62 1. Add support for `file link`
63 2. `glob` now supports the '--tails' option
64 3. Add support for `string cat`
65 4. Allow `info source` to add source info
67 Changes between 0.74 and 0.75
68 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
69 1. `binary`, `pack` and `unpack` now support floating point
70 2. `file copy` '-force' handles source and target as the same file
71 3. `format` now supports +%b+ for binary conversion
72 4. `lsort` now supports '-unique' and '-real'
73 5. Add support for half-close with `aio close` ?r|w?
74 6. Add `socket pair` for a bidirectional pipe
75 7. Add '--random-hash' to randomise hash tables for greater security
76 8. `dict` now supports 'for', 'values', 'incr', 'append', 'lappend', 'update', 'info' and 'replace'
77 9. `file stat` no longer requires the variable name
79 Changes between 0.73 and 0.74
80 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
81 1. Numbers with leading zeros are treated as decimal, not octal
83 3. Add LFS (64 bit) support for `aio seek`, `aio tell`, `aio copyto`, `file copy`
84 4. `string compare` and `string equal` now support '-length'
85 5. `glob` now supports '-directory'
87 Changes between 0.72 and 0.73
88 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
89 1. Built-in regexp now support non-capturing parentheses: (?:...)
90 2. Add `string replace`
91 3. Add `string totitle`
93 5. Add +build-jim-ext+ for easy separate building of loadable modules (extensions)
94 6. `local` now works with any command, not just procs
95 7. Add `info alias` to access the target of an alias
96 8. UTF-8 encoding past the basic multilingual plane (BMP) is supported
99 11. Most extensions are now enabled by default
100 12. Add support for namespaces and the `namespace` command
103 Changes between 0.71 and 0.72
104 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
105 1. procs now allow 'args' and optional parameters in any position
106 2. Add Tcl-compatible expr functions, `rand()`, `srand()` and `pow()`
107 3. Add support for the '-force' option to `file delete`
108 4. Better diagnostics when `source` fails to load a script with a missing quote or bracket
109 5. New +tcl_platform(pathSeparator)+
110 6. Add support settings the modification time with `file mtime`
111 7. `exec` is now fully supported on win32 (mingw32)
112 8. `file join`, `pwd`, `glob` etc. now work for mingw32
113 9. Line editing is now supported for the win32 console (mingw32)
114 10. Add `aio listen` command
116 Changes between 0.70 and 0.71
117 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
118 1. Allow 'args' to be renamed in procs
119 2. Add +$(...)+ shorthand syntax for expressions
120 3. Add automatic reference variables in procs with +&var+ syntax
121 4. Support +jimsh --version+
122 5. Additional variables in +tcl_platform()+
123 6. `local` procs now push existing commands and `upcall` can call them
124 7. Add `loop` command (TclX compatible)
125 8. Add `aio buffering` command
126 9. `info complete` can now return the missing character
127 10. `binary format` and `binary scan` are now (optionally) supported
128 11. Add `string byterange`
129 12. Built-in regexp now support non-greedy repetition (*?, +?, ??)
133 Tcl stands for 'tool command language' and is pronounced
134 'http://www.oxforddictionaries.com/definition/american_english/tickle[tickle]'.
135 It is actually two things: a language and a library.
137 First, Tcl is a simple textual language, intended primarily for
138 issuing commands to interactive programs such as text editors,
139 debuggers, illustrators, and shells. It has a simple syntax and is also
140 programmable, so Tcl users can write command procedures to provide more
141 powerful commands than those in the built-in set.
143 Second, Tcl is a library package that can be embedded in application
144 programs. The Tcl library consists of a parser for the Tcl language,
145 routines to implement the Tcl built-in commands, and procedures that
146 allow each application to extend Tcl with additional commands specific
147 to that application. The application program generates Tcl commands and
148 passes them to the Tcl parser for execution. Commands may be generated
149 by reading characters from an input source, or by associating command
150 strings with elements of the application's user interface, such as menu
151 entries, buttons, or keystrokes.
153 When the Tcl library receives commands it parses them into component
154 fields and executes built-in commands directly. For commands implemented
155 by the application, Tcl calls back to the application to execute the
156 commands. In many cases commands will invoke recursive invocations of the
157 Tcl interpreter by passing in additional strings to execute (procedures,
158 looping commands, and conditional commands all work in this way).
160 An application program gains three advantages by using Tcl for its command
161 language. First, Tcl provides a standard syntax: once users know Tcl,
162 they will be able to issue commands easily to any Tcl-based application.
163 Second, Tcl provides programmability. All a Tcl application needs
164 to do is to implement a few application-specific low-level commands.
165 Tcl provides many utility commands plus a general programming interface
166 for building up complex command procedures. By using Tcl, applications
167 need not re-implement these features.
169 Third, Tcl can be used as a common language for communicating between
170 applications. Inter-application communication is not built into the
171 Tcl core described here, but various add-on libraries, such as the Tk
172 toolkit, allow applications to issue commands to each other. This makes
173 it possible for applications to work together in much more powerful ways
174 than was previously possible.
176 Fourth, Jim Tcl includes a command processor, +jimsh+, which can be
177 used to run standalone Tcl scripts, or to run Tcl commands interactively.
179 This manual page focuses primarily on the Tcl language. It describes
180 the language syntax and the built-in commands that will be available
181 in any application based on Tcl. The individual library procedures are
182 described in more detail in separate manual pages, one per procedure.
184 JIMSH COMMAND INTERPRETER
185 -------------------------
186 A simple, but powerful command processor, +jimsh+, is part of Jim Tcl.
187 It may be invoked in interactive mode as:
191 or to process the Tcl script in a file with:
195 It may also be invoked to execute an immediate script with:
201 Interactive mode reads Tcl commands from standard input, evaluates
202 those commands and prints the results.
205 Welcome to Jim version 0.73, Copyright (c) 2005-8 Salvatore Sanfilippo
208 . lsort [info commands p*]
209 package parray pid popen proc puts pwd
210 . foreach i {a b c} {
217 invalid command name "bad"
221 If +jimsh+ is configured with line editing (it is by default) and a VT-100-compatible
222 terminal is detected, Emacs-style line editing commands are available, including:
223 arrow keys, +\^W+ to erase a word, +\^U+ to erase the line, +^R+ for reverse incremental search
224 in history. Additionally, the +h+ command may be used to display the command history.
226 Command line history is automatically saved and loaded from +~/.jim_history+
228 In interactive mode, +jimsh+ automatically runs the script +~/.jimrc+ at startup
233 The central data structure in Tcl is an interpreter (C type 'Jim_Interp').
234 An interpreter consists of a set of command bindings, a set of variable
235 values, and a few other miscellaneous pieces of state. Each Tcl command
236 is interpreted in the context of a particular interpreter.
238 Some Tcl-based applications will maintain multiple interpreters
239 simultaneously, each associated with a different widget or portion of
240 the application. Interpreters are relatively lightweight structures.
241 They can be created and deleted quickly, so application programmers should
242 feel free to use multiple interpreters if that simplifies the application.
246 Tcl supports only one type of data: strings. All commands, all arguments
247 to commands, all command results, and all variable values are strings.
249 Where commands require numeric arguments or return numeric results,
250 the arguments and results are passed as strings. Many commands expect
251 their string arguments to have certain formats, but this interpretation
252 is up to the individual commands. For example, arguments often contain
253 Tcl command strings, which may get executed as part of the commands.
254 The easiest way to understand the Tcl interpreter is to remember that
255 everything is just an operation on a string. In many cases Tcl constructs
256 will look similar to more structured constructs from other languages.
257 However, the Tcl constructs are not structured at all; they are just
258 strings of characters, and this gives them a different behaviour than
259 the structures they may look like.
261 Although the exact interpretation of a Tcl string depends on who is doing
262 the interpretation, there are three common forms that strings take:
263 commands, expressions, and lists. The major sections below discuss
264 these three forms in more detail.
268 The Tcl language has syntactic similarities to both the Unix shells
269 and Lisp. However, the interpretation of commands is different
270 in Tcl than in either of those other two systems.
271 A Tcl command string consists of one or more commands separated
272 by newline characters or semi-colons.
273 Each command consists of a collection of fields separated by
274 white space (spaces or tabs).
275 The first field must be the name of a command, and the
276 additional fields, if any, are arguments that will be passed to
277 that command. For example, the command:
281 has three fields: the first, `set`, is the name of a Tcl command, and
282 the last two, 'a' and '22', will be passed as arguments to
283 the `set` command. The command name may refer either to a built-in
284 Tcl command, an application-specific command bound in with the library
285 procedure 'Jim_CreateCommand', or a command procedure defined with the
286 `proc` built-in command.
288 Arguments are passed literally as text strings. Individual commands may
289 interpret those strings in any fashion they wish. The `set` command,
290 for example, will treat its first argument as the name of a variable
291 and its second argument as a string value to assign to that variable.
292 For other commands arguments may be interpreted as integers, lists,
293 file names, or Tcl commands.
295 Command names should normally be typed completely (e.g. no abbreviations).
296 However, if the Tcl interpreter cannot locate a command it invokes a
297 special command named `unknown` which attempts to find or create the
300 For example, at many sites `unknown` will search through library
301 directories for the desired command and create it as a Tcl procedure if
302 it is found. The `unknown` command often provides automatic completion
303 of abbreviated commands, but usually only for commands that were typed
306 It's probably a bad idea to use abbreviations in command scripts and
307 other forms that will be re-used over time: changes to the command set
308 may cause abbreviations to become ambiguous, resulting in scripts that
313 If the first non-blank character in a command is +\#+, then everything
314 from the +#+ up through the next newline character is treated as
315 a comment and ignored. When comments are embedded inside nested
316 commands (e.g. fields enclosed in braces) they must have properly-matched
317 braces (this is necessary because when Tcl parses the top-level command
318 it doesn't yet know that the nested field will be used as a command so
319 it cannot process the nested comment character as a comment).
321 GROUPING ARGUMENTS WITH DOUBLE-QUOTES
322 -------------------------------------
323 Normally each argument field ends at the next white space, but
324 double-quotes may be used to create arguments with embedded space.
326 If an argument field begins with a double-quote, then the argument isn't
327 terminated by white space (including newlines) or a semi-colon (see below
328 for information on semi-colons); instead it ends at the next double-quote
329 character. The double-quotes are not included in the resulting argument.
330 For example, the command
332 set a "This is a single argument"
334 will pass two arguments to `set`: 'a' and 'This is a single argument'.
336 Within double-quotes, command substitutions, variable substitutions,
337 and backslash substitutions still occur, as described below. If the
338 first character of a command field is not a quote, then quotes receive
339 no special interpretation in the parsing of that field.
341 GROUPING ARGUMENTS WITH BRACES
342 ------------------------------
343 Curly braces may also be used for grouping arguments. They are similar
344 to quotes except for two differences. First, they nest; this makes them
345 easier to use for complicated arguments like nested Tcl command strings.
346 Second, the substitutions described below for commands, variables, and
347 backslashes do *not* occur in arguments enclosed in braces, so braces
348 can be used to prevent substitutions where they are undesirable.
350 If an argument field begins with a left brace, then the argument ends
351 at the matching right brace. Tcl will strip off the outermost layer
352 of braces and pass the information between the braces to the command
353 without any further modification. For example, in the command
355 set a {xyz a {b c d}}
357 the `set` command will receive two arguments: 'a'
360 When braces or quotes are in effect, the matching brace or quote need
361 not be on the same line as the starting quote or brace; in this case
362 the newline will be included in the argument field along with any other
363 characters up to the matching brace or quote. For example, the `eval`
364 command takes one argument, which is a command string; `eval` invokes
365 the Tcl interpreter to execute the command string. The command
372 will assign the value '22' to 'a' and '33' to 'b'.
374 If the first character of a command field is not a left
375 brace, then neither left nor right
376 braces in the field will be treated specially (except as part of
377 variable substitution; see below).
379 COMMAND SUBSTITUTION WITH BRACKETS
380 ----------------------------------
381 If an open bracket occurs in a field of a command, then command
382 substitution occurs (except for fields enclosed in braces). All of the
383 text up to the matching close bracket is treated as a Tcl command and
384 executed immediately. Then the result of that command is substituted
385 for the bracketed text. For example, consider the command
389 When the `set` command has only a single argument, it is the name of a
390 variable and `set` returns the contents of that variable. In this case,
391 if variable 'b' has the value 'foo', then the command above is equivalent
396 Brackets can be used in more complex ways. For example, if the variable
397 'b' has the value 'foo' and the variable 'c' has the value 'gorp',
400 set a xyz[set b].[set c]
402 is equivalent to the command
407 A bracketed command may contain multiple commands separated by newlines
408 or semi-colons in the usual fashion. In this case the value of the last
409 command is used for substitution. For example, the command
414 is equivalent to the command
419 If a field is enclosed in braces then the brackets and the characters
420 between them are not interpreted specially; they are passed through to
421 the argument verbatim.
423 VARIABLE SUBSTITUTION WITH $
424 ----------------------------
425 The dollar sign (+$+) may be used as a special shorthand form for
426 substituting variable values. If +$+ appears in an argument that isn't
427 enclosed in braces then variable substitution will occur. The characters
428 after the +$+, up to the first character that isn't a number, letter,
429 or underscore, are taken as a variable name and the string value of that
430 variable is substituted for the name.
432 For example, if variable 'foo' has the value 'test', then the command
436 is equivalent to the command
440 There are two special forms for variable substitution. If the next
441 character after the name of the variable is an open parenthesis, then
442 the variable is assumed to be an array name, and all of the characters
443 between the open parenthesis and the next close parenthesis are taken as
444 an index into the array. Command substitutions and variable substitutions
445 are performed on the information between the parentheses before it is
448 For example, if the variable 'x' is an array with one element named
449 'first' and value '87' and another element named '14' and value 'more',
452 set a xyz$x(first)zyx
454 is equivalent to the command
458 If the variable 'index' has the value '14', then the command
460 set a xyz$x($index)zyx
462 is equivalent to the command
466 For more information on arrays, see VARIABLES AND ARRAYS below.
468 The second special form for variables occurs when the dollar sign is
469 followed by an open curly brace. In this case the variable name consists
470 of all the characters up to the next curly brace.
472 Array references are not possible in this form: the name between braces
473 is assumed to refer to a scalar variable. For example, if variable
474 'foo' has the value 'test', then the command
478 is equivalent to the command
483 Variable substitution does not occur in arguments that are enclosed in
484 braces: the dollar sign and variable name are passed through to the
487 The dollar sign abbreviation is simply a shorthand form. +$a+ is
488 completely equivalent to +[set a]+; it is provided as a convenience
491 SEPARATING COMMANDS WITH SEMI-COLONS
492 ------------------------------------
493 Normally, each command occupies one line (the command is terminated by a
494 newline character). However, semi-colon (+;+) is treated as a command
495 separator character; multiple commands may be placed on one line by
496 separating them with a semi-colon. Semi-colons are not treated as
497 command separators if they appear within curly braces or double-quotes.
499 BACKSLASH SUBSTITUTION
500 ----------------------
501 Backslashes may be used to insert non-printing characters into command
502 fields and also to insert special characters like braces and brackets
503 into fields without them being interpreted specially as described above.
505 The backslash sequences understood by the Tcl interpreter are
506 listed below. In each case, the backslash
507 sequence is replaced by the given character:
508 [[BackslashSequences]]
519 Carriage-return (0xd).
542 +{backslash}<space>+::
543 Space ( ): doesn't terminate argument.
546 Semi-colon: doesn't terminate command.
551 +{backslash}<newline>+::
552 Nothing: this joins two lines together
553 into a single line. This backslash feature is unique in that
554 it will be applied even when the sequence occurs within braces.
556 +{backslash}{backslash}+::
557 Backslash ('{backslash}').
560 The digits +'ddd'+ (one, two, or three of them) give the octal value of
561 the character. Note that Jim supports null characters in strings.
564 +{backslash}u\{nnn\}+::
565 +{backslash}Unnnnnnnn+::
566 The UTF-8 encoding of the unicode codepoint represented by the hex digits, +'nnnn'+, is inserted.
567 The 'u' form allows for one to four hex digits.
568 The 'U' form allows for one to eight hex digits.
569 The 'u\{nnn\}' form allows for one to eight hex digits, but makes it easier to insert
570 characters UTF-8 characters which are followed by a hex digit.
572 For example, in the command
576 the second argument to `set` will be +{x[ yza+.
578 If a backslash is followed by something other than one of the options
579 described above, then the backslash is transmitted to the argument
580 field without any special processing, and the Tcl scanner continues
581 normal processing with the next character. For example, in the
586 The first argument to `set` will be +{backslash}*a+ and the second
587 argument will be +{backslash}{foo+.
589 If an argument is enclosed in braces, then backslash sequences inside
590 the argument are parsed but no substitution occurs (except for
591 backslash-newline): the backslash
592 sequence is passed through to the argument as is, without making
593 any special interpretation of the characters in the backslash sequence.
594 In particular, backslashed braces are not counted in locating the
595 matching right brace that terminates the argument.
601 the second argument to `set` will be +{backslash}{abc+.
603 This backslash mechanism is not sufficient to generate absolutely
604 any argument structure; it only covers the
605 most common cases. To produce particularly complicated arguments
606 it is probably easiest to use the `format` command along with
607 command substitution.
609 STRING AND LIST INDEX SPECIFICATIONS
610 ------------------------------------
612 Many string and list commands take one or more 'index' parameters which
613 specify a position in the string relative to the start or end of the string/list.
615 The index may be one of the following forms:
618 A simple integer, where '0' refers to the first element of the string
621 +integer+integer+ or::
623 The sum or difference of the two integers. e.g. +2+3+ refers to the 5th element.
624 This is useful when used with (e.g.) +$i+1+ rather than the more verbose
628 The last element of the string or list.
631 The 'nth-from-last' element of the string or list.
635 1. A command is just a string.
636 2. Within a string commands are separated by newlines or semi-colons
637 (unless the newline or semi-colon is within braces or brackets
639 3. A command consists of fields. The first field is the name of the command.
640 The other fields are strings that are passed to that command as arguments.
641 4. Fields are normally separated by white space.
642 5. Double-quotes allow white space and semi-colons to appear within
644 Command substitution, variable substitution, and backslash substitution
645 still occur inside quotes.
646 6. Braces defer interpretation of special characters.
647 If a field begins with a left brace, then it consists of everything
648 between the left brace and the matching right brace. The
649 braces themselves are not included in the argument.
650 No further processing is done on the information between the braces
651 except that backslash-newline sequences are eliminated.
652 7. If a field doesn't begin with a brace then backslash,
653 variable, and command substitution are done on the field. Only a
654 single level of processing is done: the results of one substitution
655 are not scanned again for further substitutions or any other
656 special treatment. Substitution can
657 occur on any field of a command, including the command name
658 as well as the arguments.
659 8. If the first non-blank character of a command is a +\#+, everything
660 from the +#+ up through the next newline is treated as a comment
665 The second major interpretation applied to strings in Tcl is
666 as expressions. Several commands, such as `expr`, `for`,
667 and `if`, treat one or more of their arguments as expressions
668 and call the Tcl expression processors ('Jim_ExprLong',
669 'Jim_ExprBoolean', etc.) to evaluate them.
671 The operators permitted in Tcl expressions are a subset of
672 the operators permitted in C expressions, and they have the
673 same meaning and precedence as the corresponding C operators.
674 Expressions almost always yield numeric results
675 (integer or floating-point values).
676 For example, the expression
682 Tcl expressions differ from C expressions in the way that
683 operands are specified, and in that Tcl expressions support
684 non-numeric operands and string comparisons.
686 A Tcl expression consists of a combination of operands, operators,
689 White space may be used between the operands and operators and
690 parentheses; it is ignored by the expression processor.
691 Where possible, operands are interpreted as integer values.
693 Integer values may be specified in decimal (the normal case) or in
694 hexadecimal (if the first two characters of the operand are '0x').
695 Note that Jim Tcl does *not* treat numbers with leading zeros as octal.
697 If an operand does not have one of the integer formats given
698 above, then it is treated as a floating-point number if that is
699 possible. Floating-point numbers may be specified in any of the
700 ways accepted by an ANSI-compliant C compiler (except that the
701 'f', 'F', 'l', and 'L' suffixes will not be permitted in
702 most installations). For example, all of the
703 following are valid floating-point numbers: 2.1, 3., 6e4, 7.91e+16.
705 If no numeric interpretation is possible, then an operand is left
706 as a string (and only a limited set of operators may be applied to
709 1. Operands may be specified in any of the following ways:
711 2. As a numeric value, either integer or floating-point.
713 3. As a Tcl variable, using standard '$' notation.
714 The variable's value will be used as the operand.
716 4. As a string enclosed in double-quotes.
717 The expression parser will perform backslash, variable, and
718 command substitutions on the information between the quotes,
719 and use the resulting value as the operand
721 5. As a string enclosed in braces.
722 The characters between the open brace and matching close brace
723 will be used as the operand without any substitutions.
725 6. As a Tcl command enclosed in brackets.
726 The command will be executed and its result will be used as
729 Where substitutions occur above (e.g. inside quoted strings), they
730 are performed by the expression processor.
731 However, an additional layer of substitution may already have
732 been performed by the command parser before the expression
733 processor was called.
735 As discussed below, it is usually best to enclose expressions
736 in braces to prevent the command parser from performing substitutions
739 For some examples of simple expressions, suppose the variable 'a' has
740 the value 3 and the variable 'b' has the value 6. Then the expression
741 on the left side of each of the lines below will evaluate to the value
742 on the right side of the line:
747 {word one} < "word $a" 0
749 The valid operators are listed below, grouped in decreasing order
751 [[OperatorPrecedence]]
752 +int() double() round() abs(), rand(), srand()+::
753 Unary functions (except rand() which takes no arguments)
754 * +'int()'+ converts the numeric argument to an integer by truncating down.
755 * +'double()'+ converts the numeric argument to floating point.
756 * +'round()'+ converts the numeric argument to the closest integer value.
757 * +'abs()'+ takes the absolute value of the numeric argument.
758 * +'rand()'+ returns a pseudo-random floating-point value in the range (0,1).
759 * +'srand()'+ takes an integer argument to (re)seed the random number generator. Returns the first random number from that seed.
761 +sin() cos() tan() asin() acos() atan() sinh() cosh() tanh() ceil() floor() exp() log() log10() sqrt()+::
762 Unary math functions.
763 If Jim is compiled with math support, these functions are available.
766 Unary minus, unary plus, bit-wise NOT, logical NOT. None of these operands
767 may be applied to string operands, and bit-wise NOT may be
768 applied only to integers.
771 Power. e.g. 'x^y^'. If Jim is compiled with math support, supports doubles and
772 integers. Otherwise supports integers only. (Note that the math-function form
773 has the same highest precedence)
776 Multiply, divide, remainder. None of these operands may be
777 applied to string operands, and remainder may be applied only
781 Add and subtract. Valid for any numeric operands.
784 Left and right shift, left and right rotate. Valid for integer operands only.
787 Boolean less, greater, less than or equal, and greater than or equal.
788 Each operator produces 1 if the condition is true, 0 otherwise.
789 These operators may be applied to strings as well as numeric operands,
790 in which case string comparison is used.
793 Boolean equal and not equal. Each operator produces a zero/one result.
794 Valid for all operand types. *Note* that values will be converted to integers
795 if possible, then floating point types, and finally strings will be compared.
796 It is recommended that 'eq' and 'ne' should be used for string comparison.
799 String equal and not equal. Uses the string value directly without
800 attempting to convert to a number first.
803 String in list and not in list. For 'in', result is 1 if the left operand (as a string)
804 is contained in the right operand (as a list), or 0 otherwise. The result for
805 +{$a ni $list}+ is equivalent to +{!($a in $list)}+.
808 Bit-wise AND. Valid for integer operands only.
811 Bit-wise OR. Valid for integer operands only.
814 Bit-wise exclusive OR. Valid for integer operands only.
817 Logical AND. Produces a 1 result if both operands are non-zero, 0 otherwise.
818 Valid for numeric operands only (integers or floating-point).
821 Logical OR. Produces a 0 result if both operands are zero, 1 otherwise.
822 Valid for numeric operands only (integers or floating-point).
825 If-then-else, as in C. If +'x'+
826 evaluates to non-zero, then the result is the value of +'y'+.
827 Otherwise the result is the value of +'z'+.
828 The +'x'+ operand must have a numeric value, while +'y'+ and +'z'+ can
831 See the C manual for more details on the results
832 produced by each operator.
833 All of the binary operators group left-to-right within the same
834 precedence level. For example, the expression
840 The +&&+, +||+, and +?:+ operators have 'lazy evaluation', just as
841 in C, which means that operands are not evaluated if they are not
842 needed to determine the outcome. For example, in
846 only one of +[a]+ or +[b]+ will actually be evaluated,
847 depending on the value of +$v+.
849 All internal computations involving integers are done with the C
850 type 'long long' if available, or 'long' otherwise, and all internal
851 computations involving floating-point are done with the C type
854 When converting a string to floating-point, exponent overflow is
855 detected and results in a Tcl error.
856 For conversion to integer from string, detection of overflow depends
857 on the behaviour of some routines in the local C library, so it should
858 be regarded as unreliable.
859 In any case, overflow and underflow are generally not detected
860 reliably for intermediate results.
862 Conversion among internal representations for integer, floating-point,
863 and string operands is done automatically as needed.
864 For arithmetic computations, integers are used until some
865 floating-point number is introduced, after which floating-point is used.
870 yields the result 1, while
873 5 / ( [string length "abcd"] + 0.0 )
875 both yield the result 1.25.
877 String values may be used as operands of the comparison operators,
878 although the expression evaluator tries to do comparisons as integer
879 or floating-point when it can.
880 If one of the operands of a comparison is a string and the other
881 has a numeric value, the numeric operand is converted back to
882 a string using the C 'sprintf' format specifier
883 '%d' for integers and '%g' for floating-point values.
884 For example, the expressions
889 both evaluate to 1. The first comparison is done using integer
890 comparison, and the second is done using string comparison after
891 the second operand is converted to the string '18'.
893 In general it is safest to enclose an expression in braces when
894 entering it in a command: otherwise, if the expression contains
895 any white space then the Tcl interpreter will split it
896 among several arguments. For example, the command
900 results in three arguments being passed to `expr`: +$a+,
901 \+, and +$b+. In addition, if the expression isn't in braces
902 then the Tcl interpreter will perform variable and command substitution
903 immediately (it will happen in the command parser rather than in
904 the expression parser). In many cases the expression is being
905 passed to a command that will evaluate the expression later (or
906 even many times if, for example, the expression is to be used to
907 decide when to exit a loop). Usually the desired goal is to re-do
908 the variable or command substitutions each time the expression is
909 evaluated, rather than once and for all at the beginning. For example,
912 for {set i 1} $i<=10 {incr i} {...} ** WRONG **
914 is probably intended to iterate over all values of +i+ from 1 to 10.
915 After each iteration of the body of the loop, `for` will pass
916 its second argument to the expression evaluator to see whether or not
917 to continue processing. Unfortunately, in this case the value of +i+
918 in the second argument will be substituted once and for all when the
919 `for` command is parsed. If +i+ was 0 before the `for`
920 command was invoked then the second argument of `for` will be +0\<=10+
921 which will always evaluate to 1, even though +i+ eventually
922 becomes greater than 10. In the above case the loop will never
923 terminate. Instead, the expression should be placed in braces:
925 for {set i 1} {$i<=10} {incr i} {...} ** RIGHT **
927 This causes the substitution of 'i'
928 to be delayed; it will be re-done each time the expression is
929 evaluated, which is the desired result.
933 The third major way that strings are interpreted in Tcl is as lists.
934 A list is just a string with a list-like structure
935 consisting of fields separated by white space. For example, the
940 is a list with four elements or fields.
941 Lists have the same basic structure as command strings, except
942 that a newline character in a list is treated as a field separator
943 just like space or tab. Conventions for braces and quotes
944 and backslashes are the same for lists as for commands. For example,
949 is a list with three elements: +a+, +b c+, and +d e {f g h}+.
951 Whenever an element is extracted from a list, the same rules about
952 braces and quotes and backslashes are applied as for commands. Thus in
953 the example above when the third element is extracted from the list,
958 (when the field was extracted, all that happened was to strip off
959 the outermost layer of braces). Command substitution and
960 variable substitution are never
961 made on a list (at least, not by the list-processing commands; the
962 list can always be passed to the Tcl interpreter for evaluation).
964 The Tcl commands `concat`, `foreach`, `lappend`, `lindex`, `linsert`,
965 `list`, `llength`, `lrange`, `lreplace`, `lsearch`, and `lsort` allow
966 you to build lists, extract elements from them, search them, and perform
967 other list-related functions.
969 Advanced list commands include `lrepeat`, `lreverse`, `lmap`, `lassign`, `lset`.
974 A new addition to Tcl 8.5 is the ability to expand a list into separate
975 arguments. Support for this feature is also available in Jim.
977 Consider the following attempt to exec a list:
982 This will attempt to exec a command named "ls -l", which will clearly not
983 work. Typically eval and concat are required to solve this problem, however
984 it can be solved much more easily with +\{*\}+.
988 This will expand the following argument into individual elements and then evaluate
989 the resulting command.
991 Note that the official Tcl syntax is +\{*\}+, however +\{expand\}+ is retained
992 for backward compatibility with experimental versions of this feature.
996 Tcl provides two commands that support string matching using regular
997 expressions, `regexp` and `regsub`, as well as `switch -regexp` and
1000 Regular expressions may be implemented one of two ways. Either using the system's C library
1001 POSIX regular expression support, or using the built-in regular expression engine.
1002 The differences between these are described below.
1004 *NOTE* Tcl 7.x and 8.x use perl-style Advanced Regular Expressions (+ARE+).
1006 POSIX Regular Expressions
1007 ~~~~~~~~~~~~~~~~~~~~~~~~~
1008 If the system supports POSIX regular expressions, and UTF-8 support is not enabled,
1009 this support will be used by default. The type of regular expressions supported are
1010 Extended Regular Expressions (+ERE+) rather than Basic Regular Expressions (+BRE+).
1011 See REG_EXTENDED in the documentation.
1013 Using the system-supported POSIX regular expressions will typically
1014 make for the smallest code size, but some features such as UTF-8
1015 and +{backslash}w+, +{backslash}d+, +{backslash}s+ are not supported, and null characters
1016 in strings are not supported.
1018 See regex(3) and regex(7) for full details.
1020 Jim built-in Regular Expressions
1021 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1022 The Jim built-in regular expression engine may be selected with +./configure --with-jim-regexp+
1023 or it will be selected automatically if UTF-8 support is enabled.
1025 This engine supports UTF-8 as well as some +ARE+ features. The differences with both Tcl 7.x/8.x
1026 and POSIX are highlighted below.
1028 1. UTF-8 strings and patterns are both supported
1029 2. All Tcl character classes are supported (e.g. +[:alnum:]+, +[:digit:]+, +[:space:]+), but...
1030 3. Character classes apply to ASCII characters only
1031 4. Supported shorthand character classes: +{backslash}w+ = +[:alnum:]+, +{backslash}W+ = +^[:alnum:]+, +{backslash}d+ = +[:digit:],+ +{backslash}D+ = +^[:digit:],+ +{backslash}s+ = +[:space:]+, + +{backslash}S+ = +^[:space:]+
1032 5. Supported constraint escapes: +{backslash}m+ = +{backslash}<+ = start of word, +{backslash}M+ = +{backslash}>+ = end of word
1033 6. Backslash escapes may be used within regular expressions, such as +{backslash}n+ = newline, +{backslash}uNNNN+ = unicode
1034 7. Partially supported constraint escapes: +{backslash}A+ = start of string, +{backslash}Z+ = end of string
1035 8. Support for the +?+ non-greedy quantifier. e.g. +*?+
1036 9. Support for non-capturing parentheses +(?:...)+
1037 10. Jim Tcl considers that both patterns and strings end at a null character (+\x00+)
1041 Each command produces two results: a code and a string. The
1042 code indicates whether the command completed successfully or not,
1043 and the string gives additional information. The valid codes are
1044 defined in jim.h, and are:
1047 This is the normal return code, and indicates that the command completed
1048 successfully. The string gives the command's return value.
1051 Indicates that an error occurred; the string gives a message describing
1055 Indicates that the `return` command has been invoked, and that the
1056 current procedure (or top-level command or `source` command)
1057 should return immediately. The
1058 string gives the return value for the procedure or command.
1061 Indicates that the `break` command has been invoked, so the
1062 innermost loop should abort immediately. The string should always
1066 Indicates that the `continue` command has been invoked, so the
1067 innermost loop should go on to the next iteration. The string
1068 should always be empty.
1071 Indicates that a signal was caught while executing a commands.
1072 The string contains the name of the signal caught.
1073 See the `signal` and `catch` commands.
1076 Indicates that the command called the `exit` command.
1077 The string contains the exit code.
1079 Tcl programmers do not normally need to think about return codes,
1080 since +JIM_OK+ is almost always returned. If anything else is returned
1081 by a command, then the Tcl interpreter immediately stops processing
1082 commands and returns to its caller. If there are several nested
1083 invocations of the Tcl interpreter in progress, then each nested
1084 command will usually return the error to its caller, until eventually
1085 the error is reported to the top-level application code. The
1086 application will then display the error message for the user.
1088 In a few cases, some commands will handle certain `error` conditions
1089 themselves and not return them upwards. For example, the `for`
1090 command checks for the +JIM_BREAK+ code; if it occurs, then `for`
1091 stops executing the body of the loop and returns +JIM_OK+ to its
1092 caller. The `for` command also handles +JIM_CONTINUE+ codes and the
1093 procedure interpreter handles +JIM_RETURN+ codes. The `catch`
1094 command allows Tcl programs to catch errors and handle them without
1095 aborting command interpretation any further.
1097 The `info returncodes` command may be used to programmatically map between
1098 return codes and names.
1102 Tcl allows you to extend the command interface by defining
1103 procedures. A Tcl procedure can be invoked just like any other Tcl
1104 command (it has a name and it receives one or more arguments).
1105 The only difference is that its body isn't a piece of C code linked
1106 into the program; it is a string containing one or more other
1109 The `proc` command is used to create a new Tcl command procedure:
1111 +*proc* 'name arglist ?statics? body'+
1113 The new command is named +'name'+, and it replaces any existing command
1114 there may have been by that name. Whenever the new command is
1115 invoked, the contents of +'body'+ will be executed by the Tcl
1118 +'arglist'+ specifies the formal arguments to the procedure.
1119 It consists of a list, possibly empty, of the following
1120 argument specifiers:
1123 Required Argument - A simple argument name.
1126 Optional Argument - A two-element list consisting of the
1127 argument name, followed by the default value, which will
1128 be used if the corresponding argument is not supplied.
1131 Reference Argument - The caller is expected to pass the name of
1132 an existing variable. An implicit `upvar 1 'origname' 'name'` is done
1133 to make the variable available in the proc scope.
1136 Variable Argument - The special name +'args'+, which is
1137 assigned all remaining arguments (including none) as a list. The
1138 variable argument may only be specified once. Note that
1139 the syntax +args newname+ may be used to retain the special
1140 behaviour of +'args'+ with a different local name. In this case,
1141 the variable is named +'newname'+ rather than +'args'+.
1143 When the command is invoked, a local variable will be created for each of
1144 the formal arguments to the procedure; its value will be the value
1145 of corresponding argument in the invoking command or the argument's
1148 Arguments with default values need not be specified in a procedure
1149 invocation. However, there must be enough actual arguments for all
1150 required arguments, and there must not be any extra actual arguments
1151 (unless the Variable Argument is specified).
1153 Actual arguments are assigned to formal arguments as in left-to-right
1154 order with the following precedence.
1156 1. Required Arguments (including Reference Arguments)
1157 2. Optional Arguments
1158 3. Variable Argument
1160 The following example illustrates precedence. Assume a procedure declaration:
1162 proc p {{a A} args b {c C} d} {...}
1164 This procedure requires at least two arguments, but can accept an unlimited number.
1165 The following table shows how various numbers of arguments are assigned.
1166 Values marked as +-+ are assigned the default value.
1168 [width="40%",frame="topbot",options="header"]
1170 |Number of arguments|a|args|b|c|d
1178 When +'body'+ is being executed, variable names normally refer to local
1179 variables, which are created automatically when referenced and deleted
1180 when the procedure returns. One local variable is automatically created
1181 for each of the procedure's arguments. Global variables can be
1182 accessed by invoking the `global` command or via the +::+ prefix.
1186 In addition to procedure arguments, Jim procedures may declare static variables.
1187 These variables scoped to the procedure and initialised at procedure definition.
1188 Either from the static variable definition, or from the enclosing scope.
1190 Consider the following example:
1193 jim> proc a {} {a {b 2}} {
1205 The static variable +'a'+ has no initialiser, so it is initialised from
1206 the enclosing scope with the value 1. (Note that it is an error if there
1207 is no variable with the same name in the enclosing scope). However +'b'+
1208 has an initialiser, so it is initialised to 2.
1210 Unlike a local variable, the value of a static variable is retained across
1211 invocations of the procedure.
1213 See the `proc` command for information on how to define procedures
1214 and what happens when they are invoked. See also NAMESPACES.
1216 VARIABLES - SCALARS AND ARRAYS
1217 ------------------------------
1218 Tcl allows the definition of variables and the use of their values
1219 either through '$'-style variable substitution, the `set`
1220 command, or a few other mechanisms.
1222 Variables need not be declared: a new variable will automatically
1223 be created each time a new variable name is used.
1225 Tcl supports two types of variables: scalars and arrays.
1226 A scalar variable has a single value, whereas an array variable
1227 can have any number of elements, each with a name (called
1228 its 'index') and a value.
1230 Array indexes may be arbitrary strings; they need not be numeric.
1231 Parentheses are used refer to array elements in Tcl commands.
1232 For example, the command
1236 will modify the element of 'x' whose index is 'first'
1237 so that its new value is '44'.
1239 Two-dimensional arrays can be simulated in Tcl by using indexes
1240 that contain multiple concatenated values.
1241 For example, the commands
1246 set the elements of 'a' whose indexes are '2,3' and '3,6'.
1248 In general, array elements may be used anywhere in Tcl that scalar
1249 variables may be used.
1251 If an array is defined with a particular name, then there may
1252 not be a scalar variable with the same name.
1254 Similarly, if there is a scalar variable with a particular
1255 name then it is not possible to make array references to the
1258 To convert a scalar variable to an array or vice versa, remove
1259 the existing variable with the `unset` command.
1261 The `array` command provides several features for dealing
1262 with arrays, such as querying the names of all the elements of
1263 the array and converting between an array and a list.
1265 Variables may be either global or local. If a variable
1266 name is used when a procedure isn't being executed, then it
1267 automatically refers to a global variable. Variable names used
1268 within a procedure normally refer to local variables associated with that
1269 invocation of the procedure. Local variables are deleted whenever
1270 a procedure exits. Either `global` command may be used to request
1271 that a name refer to a global variable for the duration of the current
1272 procedure (this is somewhat analogous to 'extern' in C), or the variable
1273 may be explicitly scoped with the +::+ prefix. For example
1289 ARRAYS AS LISTS IN JIM
1290 ----------------------
1291 Unlike Tcl, Jim can automatically convert between a list (with an even
1292 number of elements) and an array value. This is similar to the way Tcl
1293 can convert between a string and a list.
1304 Thus `array set` is equivalent to `set` when the variable does not
1307 The reverse is also true where an array will be converted into
1310 set a(1) one; set a(2) two
1319 Tcl 8.5 introduced the dict command, and Jim Tcl has added a version
1320 of this command. Dictionaries provide efficient access to key-value
1321 pairs, just like arrays, but dictionaries are pure values. This
1322 means that you can pass them to a procedure just as a list or a
1323 string. Tcl dictionaries are therefore much more like Tcl lists,
1324 except that they represent a mapping from keys to values, rather
1325 than an ordered sequence.
1327 You can nest dictionaries, so that the value for a particular key
1328 consists of another dictionary. That way you can elegantly build
1329 complicated data structures, such as hierarchical databases. You
1330 can also combine dictionaries with other Tcl data structures. For
1331 instance, you can build a list of dictionaries that themselves
1334 Dictionaries are values that contain an efficient, order-preserving
1335 mapping from arbitrary keys to arbitrary values. Each key in the
1336 dictionary maps to a single value. They have a textual format that
1337 is exactly that of any list with an even number of elements, with
1338 each mapping in the dictionary being represented as two items in
1339 the list. When a command takes a dictionary and produces a new
1340 dictionary based on it (either returning it or writing it back into
1341 the variable that the starting dictionary was read from) the new
1342 dictionary will have the same order of keys, modulo any deleted
1343 keys and with new keys added on to the end. When a string is
1344 interpreted as a dictionary and it would otherwise have duplicate
1345 keys, only the last value for a particular key is used; the others
1346 are ignored, meaning that, "apple banana" and "apple carrot apple
1347 banana" are equivalent dictionaries (with different string
1350 Note that in Jim, arrays are implemented as dictionaries.
1351 Thus automatic conversion between lists and dictionaries applies
1352 as it does for arrays.
1354 jim> dict set a 1 one
1356 jim> dict set a 2 two
1362 jim> dict set a 3 T three
1363 1 one 2 two 3 {T three}
1365 See the `dict` command for more details.
1369 Tcl added namespaces as a mechanism avoiding name clashes, especially in applications
1370 including a number of 3rd party components. While there is less need for namespaces
1371 in Jim Tcl (which does not strive to support large applications), it is convenient to
1372 provide a subset of the support for namespaces to easy porting code from Tcl.
1374 Jim Tcl currently supports "light-weight" namespaces which should be adequate for most
1375 purposes. This feature is currently experimental. See README.namespaces for more information
1376 and the documentation of the `namespace` command.
1378 GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION
1379 -----------------------------------------------
1380 Unlike Tcl, Jim has some sophisticated support for functional programming.
1381 These are described briefly below.
1383 More information may be found at http://wiki.tcl.tk/13847
1387 A reference can be thought of as holding a value with one level of indirection,
1388 where the value may be garbage collected when unreferenced.
1389 Consider the following example:
1391 jim> set r [ref "One String" test]
1392 <reference.<test___>.00000000000000000000>
1396 The operation `ref` creates a references to the value specified by the
1397 first argument. (The second argument is a "type" used for documentation purposes).
1399 The operation `getref` is the dereferencing operation which retrieves the value
1400 stored in the reference.
1402 jim> setref $r "New String"
1407 The operation `setref` replaces the value stored by the reference. If the old value
1408 is no longer accessible by any reference, it will eventually be automatically be garbage
1413 Normally, all values in Tcl are passed by value. As such values are copied and released
1414 automatically as necessary.
1416 With the introduction of references, it is possible to create values whose lifetime
1417 transcend their scope. To support this, case, the Jim system will periodically identify
1418 and discard objects which are no longer accessible by any reference.
1420 The `collect` command may be used to force garbage collection. Consider a reference created
1423 jim> proc f {ref value} { puts "Finaliser called for $ref,$value" }
1424 jim> set r [ref "One String" test f]
1425 <reference.<test___>.00000000000
1430 Finaliser called for <reference.<test___>.00000000000,One String
1433 Note that once the reference, 'r', was modified so that it no longer
1434 contained a reference to the value, the garbage collector discarded
1435 the value (after calling the finalizer).
1437 The finalizer for a reference may be examined or changed with the `finalize` command
1441 jim> finalize $r newf
1446 Jim provides a garbage collected `lambda` function. This is a procedure
1447 which is able to create an anonymous procedure. Consider:
1449 jim> set f [lambda {a} {{x 0}} { incr x $a }]
1456 This create an anonymous procedure (with the name stored in 'f'), with a static variable
1457 which is incremented by the supplied value and the result returned.
1459 Once the procedure name is no longer accessible, it will automatically be deleted
1460 when the garbage collector runs.
1462 The procedure may also be delete immediately by renaming it "". e.g.
1468 If Jim is built with UTF-8 support enabled (configure --enable-utf),
1469 then most string-related commands become UTF-8 aware. These include,
1470 but are not limited to, `string match`, `split`, `glob`, `scan` and
1473 UTF-8 encoding has many advantages, but one of the complications is that
1474 characters can take a variable number of bytes. Thus the addition of
1475 `string bytelength` which returns the number of bytes in a string,
1476 while `string length` returns the number of characters.
1478 If UTF-8 support is not enabled, all commands treat bytes as characters
1479 and `string bytelength` returns the same value as `string length`.
1481 Note that even if UTF-8 support is not enabled, the +{backslash}uNNNN+ and related syntax
1482 is still available to embed UTF-8 sequences.
1484 Jim Tcl supports all currently defined unicode codepoints. That is 21 bits, up to +'U+1FFFFF'.
1488 Commands such as `string match`, `lsearch -glob`, `array names` and others use string
1489 pattern matching rules. These commands support UTF-8. For example:
1491 string match a\[\ua0-\ubf\]b "a\u00a3b"
1495 +format %c+ allows a unicode codepoint to be be encoded. For example, the following will return
1496 a string with two bytes and one character. The same as +{backslash}ub5+
1500 `format` respects widths as character widths, not byte widths. For example, the following will
1501 return a string with three characters, not three bytes.
1503 format %.3s \ub5\ub6\ub7\ub8
1505 Similarly, +scan ... %c+ allows a UTF-8 to be decoded to a unicode codepoint. The following will set
1506 +'a'+ to 181 (0xb5) and +'b'+ to 65 (0x41).
1508 scan \u00b5A %c%c a b
1510 `scan %s` will also accept a character class, including unicode ranges.
1514 `string is` has *not* been extended to classify UTF-8 characters. Therefore, the following
1515 will return 0, even though the string may be considered to be alphabetic.
1517 string is alpha \ub5Test
1519 This does not affect the string classes 'ascii', 'control', 'digit', 'double', 'integer' or 'xdigit'.
1521 Case Mapping and Conversion
1522 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
1523 Jim provides a simplified unicode case mapping. This means that case conversion
1524 and comparison will not increase or decrease the number of characters in a string.
1525 (Although it may change the number of bytes).
1527 `string toupper` will convert any lowercase letters to their uppercase equivalent.
1528 Any character which is not a letter or has no uppercase equivalent is left unchanged.
1529 Similarly for `string tolower` and `string totitle`.
1531 Commands which perform case insensitive matches, such as `string compare -nocase`
1532 and `lsearch -nocase` fold both strings to uppercase before comparison.
1534 Invalid UTF-8 Sequences
1535 ~~~~~~~~~~~~~~~~~~~~~~~
1536 Some UTF-8 character sequences are invalid, such as those beginning with '0xff',
1537 those which represent character sequences longer than 3 bytes (greater than U+FFFF),
1538 and those which end prematurely, such as a lone '0xc2'.
1540 In these situations, the offending bytes are treated as single characters. For example,
1541 the following returns 2.
1543 string bytelength \xff\xff
1547 If UTF-8 support is enabled, the built-in regular expression engine will be
1548 selected which supports UTF-8 strings and patterns.
1550 See REGULAR EXPRESSIONS
1554 The Tcl library provides the following built-in commands, which will
1555 be available in any application using Tcl. In addition to these
1556 built-in commands, there may be additional commands defined by each
1557 application, plus commands defined as Tcl procedures.
1559 In the command syntax descriptions below, words in +*boldface*+ are
1560 literals that you type verbatim to Tcl.
1562 Words in +'italics'+ are meta-symbols; they serve as names for any of
1563 a range of values that you can type.
1565 Optional arguments or groups of arguments are indicated by enclosing them
1566 in +?question-marks?+.
1568 Ellipses (+\...+) indicate that any number of additional
1569 arguments or groups of arguments may appear, in the same format
1570 as the preceding argument(s).
1581 Delivers the +SIGALRM+ signal to the process after the given
1582 number of seconds. If the platform supports 'ualarm(3)' then
1583 the argument may be a floating point value. Otherwise it must
1586 Note that unless a signal handler for +SIGALRM+ has been installed
1587 (see `signal`), the process will exit on this signal.
1591 +*alias* 'name args\...'+
1593 Creates a single word alias (command) for one or more words. For example,
1594 the following creates an alias for the command `info exists`.
1601 `alias` returns +'name'+, allowing it to be used with `local`.
1603 See also `proc`, `curry`, `lambda`, `local`, `info alias`, `exists -alias`
1607 +*append* 'varName value ?value value ...?'+
1609 Append all of the +'value'+ arguments to the current value
1610 of variable +'varName'+. If +'varName'+ doesn't exist,
1611 it is given a value equal to the concatenation of all the
1612 +'value'+ arguments.
1614 This command provides an efficient way to build up long
1615 variables incrementally.
1616 For example, "`append a $b`" is much more efficient than
1617 "`set a $a$b`" if +$a+ is long.
1621 +*apply* 'lambdaExpr ?arg1 arg2 \...?'+
1623 The command `apply` provides for anonymous procedure calls,
1624 similar to `lambda`, but without command name being created, even temporarily.
1626 The function +'lambdaExpr'+ is a two element list +{args body}+
1627 or a three element list +{args body namespace}+. The first element
1628 args specifies the formal arguments, in the same form as the `proc` and `lambda` commands.
1632 +*array* 'option arrayName ?arg\...?'+
1634 This command performs one of several operations on the
1635 variable given by +'arrayName'+.
1637 Note that in general, if the named array does not exist, the +'array'+ command behaves
1638 as though the array exists but is empty.
1640 The +'option'+ argument determines what action is carried out by the
1641 command. The legal +'options'+ (which may be abbreviated) are:
1643 +*array exists* 'arrayName'+::
1644 Returns 1 if arrayName is an array variable, 0 if there is
1645 no variable by that name. This command is essentially
1646 identical to `info exists`
1648 +*array get* 'arrayName ?pattern?'+::
1649 Returns a list containing pairs of elements. The first
1650 element in each pair is the name of an element in arrayName
1651 and the second element of each pair is the value of the
1652 array element. The order of the pairs is undefined. If
1653 pattern is not specified, then all of the elements of the
1654 array are included in the result. If pattern is specified,
1655 then only those elements whose names match pattern (using
1656 the matching rules of string match) are included. If arrayName
1657 isn't the name of an array variable, or if the array contains
1658 no elements, then an empty list is returned.
1660 +*array names* 'arrayName ?pattern?'+::
1661 Returns a list containing the names of all of the elements
1662 in the array that match pattern. If pattern is omitted then
1663 the command returns all of the element names in the array.
1664 If pattern is specified, then only those elements whose
1665 names match pattern (using the matching rules of string
1666 match) are included. If there are no (matching) elements
1667 in the array, or if arrayName isn't the name of an array
1668 variable, then an empty string is returned.
1670 +*array set* 'arrayName list'+::
1671 Sets the values of one or more elements in arrayName. list
1672 must have a form like that returned by array get, consisting
1673 of an even number of elements. Each odd-numbered element
1674 in list is treated as an element name within arrayName, and
1675 the following element in list is used as a new value for
1676 that array element. If the variable arrayName does not
1677 already exist and list is empty, arrayName is created with
1678 an empty array value.
1680 +*array size* 'arrayName'+::
1681 Returns the number of elements in the array. If arrayName
1682 isn't the name of an array then 0 is returned.
1684 +*array unset* 'arrayName ?pattern?'+::
1685 Unsets all of the elements in the array that match pattern
1686 (using the matching rules of string match). If arrayName
1687 isn't the name of an array variable or there are no matching
1688 elements in the array, no error will be raised. If pattern
1689 is omitted and arrayName is an array variable, then the
1690 command unsets the entire array. The command always returns
1697 This command may be invoked only inside the body of a loop command
1698 such as `for` or `foreach` or `while`. It returns a +JIM_BREAK+ code
1699 to signal the innermost containing loop command to return immediately.
1703 +*case* 'string' ?in? 'patList body ?patList body ...?'+
1705 +*case* 'string' ?in? {'patList body ?patList body ...?'}+
1707 *Note* that the `switch` command should generally be preferred unless compatibility
1708 with Tcl 6.x is desired.
1710 Match +'string'+ against each of the +'patList'+ arguments
1711 in order. If one matches, then evaluate the following +'body'+ argument
1712 by passing it recursively to the Tcl interpreter, and return the result
1713 of that evaluation. Each +'patList'+ argument consists of a single
1714 pattern or list of patterns. Each pattern may contain any of the wild-cards
1715 described under `string match`.
1717 If a +'patList'+ argument is +default+, the corresponding body will be
1718 evaluated if no +'patList'+ matches +'string'+. If no +'patList'+ argument
1719 matches +'string'+ and no default is given, then the `case` command returns
1722 Two syntaxes are provided.
1724 The first uses a separate argument for each of the patterns and commands;
1725 this form is convenient if substitutions are desired on some of the
1726 patterns or commands.
1728 The second form places all of the patterns and commands together into
1729 a single argument; the argument must have proper list structure, with
1730 the elements of the list being the patterns and commands.
1732 The second form makes it easy to construct multi-line case commands,
1733 since the braces around the whole list make it unnecessary to include a
1734 backslash at the end of each line.
1736 Since the +'patList'+ arguments are in braces in the second form,
1737 no command or variable substitutions are performed on them; this makes
1738 the behaviour of the second form different than the first form in some
1741 Below are some examples of `case` commands:
1743 case abc in {a b} {format 1} default {format 2} a* {format 3}
1753 will return '1', and
1768 +*catch* ?-?no?'code \...'? ?--? 'command ?resultVarName? ?optionsVarName?'+
1770 The `catch` command may be used to prevent errors from aborting
1771 command interpretation. `catch` evaluates +'command'+, and returns a
1772 +JIM_OK+ code, regardless of any errors that might occur while
1773 executing +'command'+ (with the possible exception of +JIM_SIGNAL+ -
1776 The return value from `catch` is a decimal string giving the code
1777 returned by the Tcl interpreter after executing +'command'+. This
1778 will be '0' (+JIM_OK+) if there were no errors in +'command'+; otherwise
1779 it will have a non-zero value corresponding to one of the exceptional
1780 return codes (see jim.h for the definitions of code values, or the
1781 `info returncodes` command).
1783 If the +'resultVarName'+ argument is given, then it gives the name
1784 of a variable; `catch` will set the value of the variable to the
1785 string returned from +'command'+ (either a result or an error message).
1787 If the +'optionsVarName'+ argument is given, then it gives the name
1788 of a variable; `catch` will set the value of the variable to a
1789 dictionary. For any return code other than +JIM_RETURN+, the value
1790 for the key +-code+ will be set to the return code. For +JIM_RETURN+
1791 it will be set to the code given in `return -code`. Additionally,
1792 for the return code +JIM_ERR+, the value of the key +-errorinfo+
1793 will contain the current stack trace (the same result as `info stacktrace`),
1794 the value of the key +-errorcode+ will contain the
1795 same value as the global variable $::errorCode, and the value of
1796 the key +-level+ will be the current return level (see `return -level`).
1797 This can be useful to rethrow an error:
1799 if {[catch {...} msg opts]} {
1800 ...maybe do something with the error...
1802 return {*}$opts $msg
1805 Normally `catch` will +'not'+ catch any of the codes +JIM_EXIT+, +JIM_EVAL+ or +JIM_SIGNAL+.
1806 The set of codes which will be caught may be modified by specifying the one more codes before
1809 e.g. To catch +JIM_EXIT+ but not +JIM_BREAK+ or +JIM_CONTINUE+
1811 catch -exit -nobreak -nocontinue -- { ... }
1813 The use of +--+ is optional. It signifies that no more return code options follow.
1815 Note that if a signal marked as `signal handle` is caught with `catch -signal`, the return value
1816 (stored in +'resultVarName'+) is name of the signal caught.
1822 Change the current working directory to +'dirName'+.
1824 Returns an empty string.
1826 This command can potentially be disruptive to an application, so it may
1827 be removed in some applications.
1832 Returns the current time as seconds since the epoch.
1835 Returns the current time in `clicks'.
1837 +*clock microseconds*+::
1838 Returns the current time in microseconds.
1840 +*clock milliseconds*+::
1841 Returns the current time in milliseconds.
1843 +*clock format* 'seconds' ?*-format* 'format?'+::
1844 Format the given time (seconds since the epoch) according to the given
1845 format. See strftime(3) for supported formats.
1846 If no format is supplied, "%c" is used.
1848 +*clock scan* 'str' *-format* 'format'+::
1849 Scan the given time string using the given format string.
1850 See strptime(3) for supported formats.
1858 Closes the file given by +'fileId'+.
1859 +'fileId'+ must be the return value from a previous invocation
1860 of the `open` command; after this command, it should not be
1867 Normally reference garbage collection is automatically performed periodically.
1868 However it may be run immediately with the `collect` command.
1870 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
1874 +*concat* 'arg ?arg \...?'+
1876 This command treats each argument as a list and concatenates them
1877 into a single list. It permits any number of arguments. For example,
1880 concat a b {c d e} {f {g h}}
1892 This command may be invoked only inside the body of a loop command such
1893 as `for` or `foreach` or `while`. It returns a +JIM_CONTINUE+ code to
1894 signal the innermost containing loop command to skip the remainder of
1895 the loop's body but continue with the next iteration of the loop.
1899 +*alias* 'args\...'+
1901 Similar to `alias` except it creates an anonymous procedure (lambda) instead of
1904 the following creates a local, unnamed alias for the command `info exists`.
1906 set e [local curry info exists]
1911 `curry` returns the name of the procedure.
1913 See also `proc`, `alias`, `lambda`, `local`.
1917 +*dict* 'option ?arg\...?'+
1919 Performs one of several operations on dictionary values.
1921 The +'option'+ argument determines what action is carried out by the
1922 command. The legal +'options'+ are:
1924 +*dict create* '?key value \...?'+::
1925 Create and return a new dictionary value that contains each of
1926 the key/value mappings listed as arguments (keys and values
1927 alternating, with each key being followed by its associated
1930 +*dict exists* 'dictionary key ?key \...?'+::
1931 Returns a boolean value indicating whether the given key (or path
1932 of keys through a set of nested dictionaries) exists in the given
1933 dictionary value. This returns a true value exactly when `dict get`
1934 on that path will succeed.
1936 +*dict get* 'dictionary ?key \...?'+::
1937 Given a dictionary value (first argument) and a key (second argument),
1938 this will retrieve the value for that key. Where several keys are
1939 supplied, the behaviour of the command shall be as if the result
1940 of "`dict get $dictVal $key`" was passed as the first argument to
1941 dict get with the remaining arguments as second (and possibly
1942 subsequent) arguments. This facilitates lookups in nested dictionaries.
1943 If no keys are provided, dict would return a list containing pairs
1944 of elements in a manner similar to array get. That is, the first
1945 element of each pair would be the key and the second element would
1946 be the value for that key. It is an error to attempt to retrieve
1947 a value for a key that is not present in the dictionary.
1949 +*dict keys* 'dictionary ?pattern?'+::
1950 Returns a list of the keys in the dictionary.
1951 If pattern is specified, then only those keys whose
1952 names match +'pattern'+ (using the matching rules of string
1953 match) are included.
1955 +*dict merge* ?'dictionary \...'?+::
1956 Return a dictionary that contains the contents of each of the
1957 +'dictionary'+ arguments. Where two (or more) dictionaries
1958 contain a mapping for the same key, the resulting dictionary
1959 maps that key to the value according to the last dictionary on
1960 the command line containing a mapping for that key.
1962 +*dict set* 'dictionaryName key ?key \...? value'+::
1963 This operation takes the +'name'+ of a variable containing a dictionary
1964 value and places an updated dictionary value in that variable
1965 containing a mapping from the given key to the given value. When
1966 multiple keys are present, this operation creates or updates a chain
1967 of nested dictionaries.
1969 +*dict size* 'dictionary'+::
1970 Return the number of key/value mappings in the given dictionary value.
1972 +*dict unset* 'dictionaryName key ?key \...? value'+::
1973 This operation (the companion to `dict set`) takes the name of a
1974 variable containing a dictionary value and places an updated
1975 dictionary value in that variable that does not contain a mapping
1976 for the given key. Where multiple keys are present, this describes
1977 a path through nested dictionaries to the mapping to remove. At
1978 least one key must be specified, but the last key on the key-path
1979 need not exist. All other components on the path must exist.
1981 +*dict with* 'dictionaryName key ?key \...? script'+::
1982 Execute the Tcl script in +'script'+ with the value for each
1983 key in +'dictionaryName'+ mapped to a variable with the same
1984 name. Where one or more keys are given, these indicate a chain
1985 of nested dictionaries, with the innermost dictionary being the
1986 one opened out for the execution of body. Making +'dictionaryName'+
1987 unreadable will make the updates to the dictionary be discarded,
1988 and this also happens if the contents of +'dictionaryName'+ are
1989 adjusted so that the chain of dictionaries no longer exists.
1990 The result of `dict with` is (unless some kind of error occurs)
1991 the result of the evaluation of body.
1993 The variables are mapped in the scope enclosing the `dict with`;
1994 it is recommended that this command only be used in a local
1995 scope (procedure). Because of this, the variables set by
1996 `dict with` will continue to exist after the command finishes (unless
1997 explicitly unset). Note that changes to the contents of +'dictionaryName'+
1998 only happen when +'script'+ terminates.
2000 +*dict for, values, incr, append, lappend, update, info, replace*+ to be documented...
2004 +*env* '?name? ?default?'+
2006 If +'name'+ is supplied, returns the value of +'name'+ from the initial
2007 environment (see getenv(3)). An error is returned if +'name'+ does not
2008 exist in the environment, unless +'default'+ is supplied - in which case
2009 that value is returned instead.
2011 If no arguments are supplied, returns a list of all environment variables
2012 and their values as +{name value \...}+
2014 See also the global variable +::env+
2022 Returns 1 if an end-of-file condition has occurred on +'fileId'+,
2025 +'fileId'+ must have been the return value from a previous call to `open`,
2026 or it may be +stdin+, +stdout+, or +stderr+ to refer to one of the
2027 standard I/O channels.
2031 +*error* 'message ?stacktrace?'+
2033 Returns a +JIM_ERR+ code, which causes command interpretation to be
2034 unwound. +'message'+ is a string that is returned to the application
2035 to indicate what went wrong.
2037 If the +'stacktrace'+ argument is provided and is non-empty,
2038 it is used to initialize the stacktrace.
2040 This feature is most useful in conjunction with the `catch` command:
2041 if a caught error cannot be handled successfully, +'stacktrace'+ can be used
2042 to return a stack trace reflecting the original point of occurrence
2047 error $errMsg [info stacktrace]
2049 See also `errorInfo`, `info stacktrace`, `catch` and `return`
2053 +*errorInfo* 'error ?stacktrace?'+
2055 Returns a human-readable representation of the given error message and stack trace.
2058 if {[catch {...} error]} {
2059 puts stderr [errorInfo $error [info stacktrace]]
2067 +*eval* 'arg ?arg\...?'+
2069 `eval` takes one or more arguments, which together comprise a Tcl
2070 command (or collection of Tcl commands separated by newlines in the
2071 usual way). `eval` concatenates all its arguments in the same
2072 fashion as the `concat` command, passes the concatenated string to the
2073 Tcl interpreter recursively, and returns the result of that
2074 evaluation (or any error generated by it).
2078 +*exec* 'arg ?arg\...?'+
2080 This command treats its arguments as the specification
2081 of one or more UNIX commands to execute as subprocesses.
2082 The commands take the form of a standard shell pipeline;
2083 +|+ arguments separate commands in the
2084 pipeline and cause standard output of the preceding command
2085 to be piped into standard input of the next command (or +|&+ for
2086 both standard output and standard error).
2088 Under normal conditions the result of the `exec` command
2089 consists of the standard output produced by the last command
2090 in the pipeline followed by the standard error output.
2092 If any of the commands writes to its standard error file,
2093 then this will be included in the result after the standard output
2094 of the last command.
2096 Note that unlike Tcl, data written to standard error does not cause
2097 `exec` to return an error.
2099 If any of the commands in the pipeline exit abnormally or
2100 are killed or suspended, then `exec` will return an error.
2101 If no standard error output was produced, or is redirected,
2102 the error message will include the normal result, as above,
2103 followed by error messages describing the abnormal terminations.
2105 If any standard error output was produced, these abnormal termination
2106 messages are suppressed.
2108 If the last character of the result or error message
2109 is a newline then that character is deleted from the result
2110 or error message for consistency with normal
2113 An +'arg'+ may have one of the following special forms:
2116 The standard output of the last command in the pipeline
2117 is redirected to the file. In this situation `exec`
2118 will normally return an empty string.
2121 As above, but append to the file.
2124 The standard output of the last command in the pipeline is
2125 redirected to the given (writable) file descriptor (e.g. stdout,
2126 stderr, or the result of `open`). In this situation `exec`
2127 will normally return an empty string.
2130 The standard error of the last command in the pipeline
2131 is redirected to the file.
2134 As above, but append to the file.
2137 The standard error of the last command in the pipeline is
2138 redirected to the given (writable) file descriptor.
2141 The standard error of the last command in the pipeline is
2142 redirected to the same file descriptor as the standard output.
2145 Both the standard output and standard error of the last command
2146 in the pipeline is redirected to the file.
2149 As above, but append to the file.
2152 The standard input of the first command in the pipeline
2153 is taken from the file.
2156 The standard input of the first command is taken as the
2157 given immediate value.
2160 The standard input of the first command in the pipeline
2161 is taken from the given (readable) file descriptor.
2163 If there is no redirection of standard input, standard error
2164 or standard output, these are connected to the corresponding
2165 input or output of the application.
2167 If the last +'arg'+ is +&+ then the command will be
2168 executed in background.
2169 In this case the standard output from the last command
2170 in the pipeline will
2171 go to the application's standard output unless
2172 redirected in the command, and error output from all
2173 the commands in the pipeline will go to the application's
2174 standard error file. The return value of exec in this case
2175 is a list of process ids (pids) in the pipeline.
2177 Each +'arg'+ becomes one word for a command, except for
2178 +|+, +<+, +<<+, +>+, and +&+ arguments, and the
2179 arguments that follow +<+, +<<+, and +>+.
2181 The first word in each command is taken as the command name;
2182 the directories in the PATH environment variable are searched for
2183 an executable by the given name.
2185 No `glob` expansion or other shell-like substitutions
2186 are performed on the arguments to commands.
2188 If the command fails, the global $::errorCode (and the -errorcode
2189 option in `catch`) will be set to a list, as follows:
2191 +*CHILDKILLED* 'pid sigName msg'+::
2192 This format is used when a child process has been killed
2193 because of a signal. The pid element will be the process's
2194 identifier (in decimal). The sigName element will be the
2195 symbolic name of the signal that caused the process to
2196 terminate; it will be one of the names from the include
2197 file signal.h, such as SIGPIPE. The msg element will be a
2198 short human-readable message describing the signal, such
2199 as "write on pipe with no readers" for SIGPIPE.
2201 +*CHILDSUSP* 'pid sigName msg'+::
2202 This format is used when a child process has been suspended
2203 because of a signal. The pid element will be the process's
2204 identifier, in decimal. The sigName element will be the
2205 symbolic name of the signal that caused the process to
2206 suspend; this will be one of the names from the include
2207 file signal.h, such as SIGTTIN. The msg element will be a
2208 short human-readable message describing the signal, such
2209 as "background tty read" for SIGTTIN.
2211 +*CHILDSTATUS* 'pid code'+::
2212 This format is used when a child process has exited with a
2213 non-zero exit status. The pid element will be the process's
2214 identifier (in decimal) and the code element will be the
2215 exit code returned by the process (also in decimal).
2217 The environment for the executed command is set from $::env (unless
2218 this variable is unset, in which case the original environment is used).
2222 +*exists ?-var|-proc|-command|-alias?* 'name'+
2224 Checks the existence of the given variable, procedure, command
2225 or alias respectively and returns 1 if it exists or 0 if not. This command
2226 provides a more simplified/convenient version of `info exists`,
2227 `info procs` and `info commands`.
2229 If the type is omitted, a type of '-var' is used. The type may be abbreviated.
2233 +*exit* '?returnCode?'+
2235 Terminate the process, returning +'returnCode'+ to the
2236 parent as the exit status.
2238 If +'returnCode'+ isn't specified then it defaults
2241 Note that exit can be caught with `catch`.
2247 Calls the expression processor to evaluate +'arg'+, and returns
2248 the result as a string. See the section EXPRESSIONS above.
2250 Note that Jim supports a shorthand syntax for `expr` as +$(\...)+
2251 The following two are identical.
2253 set x [expr {3 * 2 + 1}]
2258 +*file* 'option name ?arg\...?'+
2260 Operate on a file or a file name. +'name'+ is the name of a file.
2262 +'option'+ indicates what to do with the file name. Any unique
2263 abbreviation for +'option'+ is acceptable. The valid options are:
2265 +*file atime* 'name'+::
2266 Return a decimal string giving the time at which file +'name'+
2267 was last accessed. The time is measured in the standard UNIX
2268 fashion as seconds from a fixed starting time (often January 1, 1970).
2269 If the file doesn't exist or its access time cannot be queried then an
2272 +*file copy ?-force?* 'source target'+::
2273 Copies file +'source'+ to file +'target'+. The source file must exist.
2274 The target file must not exist, unless +-force+ is specified.
2276 +*file delete ?-force? ?--?* 'name\...'+::
2277 Deletes file or directory +'name'+. If the file or directory doesn't exist, nothing happens.
2278 If it can't be deleted, an error is generated. Non-empty directories will not be deleted
2279 unless the +-force+ options is given. In this case no errors will be generated, even
2280 if the file/directory can't be deleted. Use +'--'+ if there is any possibility of
2281 the first name being +'-force'+.
2283 +*file dirname* 'name'+::
2284 Return all of the characters in +'name'+ up to but not including
2285 the last slash character. If there are no slashes in +'name'+
2286 then return +.+ (a single dot). If the last slash in +'name'+ is its first
2287 character, then return +/+.
2289 +*file executable* 'name'+::
2290 Return '1' if file +'name'+ is executable by
2291 the current user, '0' otherwise.
2293 +*file exists* 'name'+::
2294 Return '1' if file +'name'+ exists and the current user has
2295 search privileges for the directories leading to it, '0' otherwise.
2297 +*file extension* 'name'+::
2298 Return all of the characters in +'name'+ after and including the
2299 last dot in +'name'+. If there is no dot in +'name'+ then return
2302 +*file isdirectory* 'name'+::
2303 Return '1' if file +'name'+ is a directory,
2306 +*file isfile* 'name'+::
2307 Return '1' if file +'name'+ is a regular file,
2310 +*file join* 'arg\...'+::
2311 Joins multiple path components. Note that if any components is
2312 an absolute path, the preceding components are ignored.
2313 Thus +"`file` join /tmp /root"+ returns +"/root"+.
2315 +*file link* ?*-hard|-symbolic*? 'newname target'+::
2316 Creates a hard link (default) or symbolic link from +'newname'+ to +'target'+.
2317 Note that the sense of this command is the opposite of `file rename` and `file copy`
2318 and also of `ln`, but this is compatible with Tcl.
2319 An error is returned if +'target'+ doesn't exist or +'newname'+ already exists.
2321 +*file lstat* 'name varName'+::
2322 Same as 'stat' option (see below) except uses the +'lstat'+
2323 kernel call instead of +'stat'+. This means that if +'name'+
2324 refers to a symbolic link the information returned in +'varName'+
2325 is for the link rather than the file it refers to. On systems that
2326 don't support symbolic links this option behaves exactly the same
2327 as the 'stat' option.
2329 +*file mkdir* 'dir1 ?dir2\...?'+::
2330 Creates each directory specified. For each pathname +'dir'+ specified,
2331 this command will create all non-existing parent directories
2332 as well as +'dir'+ itself. If an existing directory is specified,
2333 then no action is taken and no error is returned. Trying to
2334 overwrite an existing file with a directory will result in an
2335 error. Arguments are processed in the order specified, halting
2336 at the first error, if any.
2338 +*file mtime* 'name ?time?'+::
2339 Return a decimal string giving the time at which file +'name'+
2340 was last modified. The time is measured in the standard UNIX
2341 fashion as seconds from a fixed starting time (often January 1, 1970).
2342 If the file doesn't exist or its modified time cannot be queried then an
2343 error is generated. If +'time'+ is given, sets the modification time
2344 of the file to the given value.
2346 +*file normalize* 'name'+::
2347 Return the normalized path of +'name'+. See 'realpath(3)'.
2349 +*file owned* 'name'+::
2350 Return '1' if file +'name'+ is owned by the current user,
2353 +*file readable* 'name'+::
2354 Return '1' if file +'name'+ is readable by
2355 the current user, '0' otherwise.
2357 +*file readlink* 'name'+::
2358 Returns the value of the symbolic link given by +'name'+ (i.e. the
2359 name of the file it points to). If
2360 +'name'+ isn't a symbolic link or its value cannot be read, then
2361 an error is returned. On systems that don't support symbolic links
2362 this option is undefined.
2364 +*file rename* ?*-force*? 'oldname' 'newname'+::
2365 Renames the file from the old name to the new name.
2366 If +'newname'+ already exists, an error is returned unless +'-force'+ is
2369 +*file rootname* 'name'+::
2370 Return all of the characters in +'name'+ up to but not including
2371 the last '.' character in the name. If +'name'+ doesn't contain
2372 a dot, then return +'name'+.
2374 +*file size* 'name'+::
2375 Return a decimal string giving the size of file +'name'+ in bytes.
2376 If the file doesn't exist or its size cannot be queried then an
2379 +*file stat* 'name ?varName?'+::
2380 Invoke the 'stat' kernel call on +'name'+, and return the result
2381 as a dictionary with the following keys: 'atime',
2382 'ctime', 'dev', 'gid', 'ino', 'mode', 'mtime',
2383 'nlink', 'size', 'type', 'uid'.
2384 Each element except 'type' is a decimal string with the value of
2385 the corresponding field from the 'stat' return structure; see the
2386 manual entry for 'stat' for details on the meanings of the values.
2387 The 'type' element gives the type of the file in the same form
2388 returned by the command `file type`.
2389 If +'varName'+ is specified, it is taken to be the name of an array
2390 variable and the values are also stored into the array.
2392 +*file tail* 'name'+::
2393 Return all of the characters in +'name'+ after the last slash.
2394 If +'name'+ contains no slashes then return +'name'+.
2396 +*file tempfile* '?template?'+::
2397 Creates and returns the name of a unique temporary file. If +'template'+ is omitted, a
2398 default template will be used to place the file in /tmp. See 'mkstemp(3)' for
2399 the format of the template and security concerns.
2401 +*file type* 'name'+::
2402 Returns a string giving the type of file +'name'+, which will be
2403 one of +file+, +directory+, +characterSpecial+,
2404 +blockSpecial+, +fifo+, +link+, or +socket+.
2406 +*file writable* 'name'+::
2407 Return '1' if file +'name'+ is writable by
2408 the current user, '0' otherwise.
2410 The `file` commands that return 0/1 results are often used in
2411 conditional or looping commands, for example:
2413 if {![file exists foo]} {
2414 error {bad file name}
2421 +*finalize* 'reference ?command?'+
2423 If +'command'+ is omitted, returns the finalizer command for the given reference.
2425 Otherwise, sets a new finalizer command for the given reference. +'command'+ may be
2426 the empty string to remove the current finalizer.
2428 The reference must be a valid reference create with the `ref`
2431 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2439 Flushes any output that has been buffered for +'fileId'+. +'fileId'+ must
2440 have been the return value from a previous call to `open`, or it may be
2441 +stdout+ or +stderr+ to access one of the standard I/O streams; it must
2442 refer to a file that was opened for writing. This command returns an
2447 +*for* 'start test next body'+
2449 `for` is a looping command, similar in structure to the C `for` statement.
2450 The +'start'+, +'next'+, and +'body'+ arguments must be Tcl command strings,
2451 and +'test'+ is an expression string.
2453 The `for` command first invokes the Tcl interpreter to execute +'start'+.
2454 Then it repeatedly evaluates +'test'+ as an expression; if the result is
2455 non-zero it invokes the Tcl interpreter on +'body'+, then invokes the Tcl
2456 interpreter on +'next'+, then repeats the loop. The command terminates
2457 when +'test'+ evaluates to 0.
2459 If a `continue` command is invoked within +'body'+ then any remaining
2460 commands in the current execution of +'body'+ are skipped; processing
2461 continues by invoking the Tcl interpreter on +'next'+, then evaluating
2462 +'test'+, and so on.
2464 If a `break` command is invoked within +'body'+ or +'next'+, then the `for`
2465 command will return immediately.
2467 The operation of `break` and `continue` are similar to the corresponding
2470 `for` returns an empty string.
2474 +*foreach* 'varName list body'+
2476 +*foreach* 'varList list ?varList2 list2 \...? body'+
2478 In this command, +'varName'+ is the name of a variable, +'list'+
2479 is a list of values to assign to +'varName'+, and +'body'+ is a
2480 collection of Tcl commands.
2482 For each field in +'list'+ (in order from left to right), `foreach` assigns
2483 the contents of the field to +'varName'+ (as if the `lindex` command
2484 had been used to extract the field), then calls the Tcl interpreter to
2487 If instead of being a simple name, +'varList'+ is used, multiple assignments
2488 are made each time through the loop, one for each element of +'varList'+.
2490 For example, if there are two elements in +'varList'+ and six elements in
2491 the list, the loop will be executed three times.
2493 If the length of the list doesn't evenly divide by the number of elements
2494 in +'varList'+, the value of the remaining variables in the last iteration
2495 of the loop are undefined.
2497 The `break` and `continue` statements may be invoked inside +'body'+,
2498 with the same effect as in the `for` command.
2500 `foreach` returns an empty string.
2504 +*format* 'formatString ?arg \...?'+
2506 This command generates a formatted string in the same way as the
2507 C 'sprintf' procedure (it uses 'sprintf' in its
2508 implementation). +'formatString'+ indicates how to format
2509 the result, using +%+ fields as in 'sprintf', and the additional
2510 arguments, if any, provide values to be substituted into the result.
2512 All of the 'sprintf' options are valid; see the 'sprintf'
2513 man page for details. Each +'arg'+ must match the expected type
2514 from the +%+ field in +'formatString'+; the `format` command
2515 converts each argument to the correct type (floating, integer, etc.)
2516 before passing it to 'sprintf' for formatting.
2518 The only unusual conversion is for +%c+; in this case the argument
2519 must be a decimal string, which will then be converted to the corresponding
2520 ASCII (or UTF-8) character value.
2522 In addition, Jim Tcl provides basic support for conversion to binary with +%b+.
2524 `format` does backslash substitution on its +'formatString'+
2525 argument, so backslash sequences in +'formatString'+ will be handled
2526 correctly even if the argument is in braces.
2528 The return value from `format` is the formatted string.
2532 +*getref* 'reference'+
2534 Returns the string associated with +'reference'+. The reference must
2535 be a valid reference create with the `ref` command.
2537 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2541 +*gets* 'fileId ?varName?'+
2543 +'fileId' *gets* '?varName?'+
2545 Reads the next line from the file given by +'fileId'+ and discards
2546 the terminating newline character.
2548 If +'varName'+ is specified, then the line is placed in the variable
2549 by that name and the return value is a count of the number of characters
2550 read (not including the newline).
2552 If the end of the file is reached before reading
2553 any characters then -1 is returned and +'varName'+ is set to an
2556 If +'varName'+ is not specified then the return value will be
2557 the line (minus the newline character) or an empty string if
2558 the end of the file is reached before reading any characters.
2560 An empty string will also be returned if a line contains no characters
2561 except the newline, so `eof` may have to be used to determine
2562 what really happened.
2564 If the last character in the file is not a newline character, then
2565 `gets` behaves as if there were an additional newline character
2566 at the end of the file.
2568 +'fileId'+ must be +stdin+ or the return value from a previous
2569 call to `open`; it must refer to a file that was opened
2574 +*glob* ?*-nocomplain*? ?*-directory* 'dir'? ?*-tails*? ?*--*? 'pattern ?pattern \...?'+
2576 This command performs filename globbing, using csh rules. The returned
2577 value from `glob` is the list of expanded filenames.
2579 If +-nocomplain+ is specified as the first argument then an empty
2580 list may be returned; otherwise an error is returned if the expanded
2581 list is empty. The +-nocomplain+ argument must be provided
2582 exactly: an abbreviation will not be accepted.
2584 If +-directory+ is given, the +'dir'+ is understood to contain a
2585 directory name to search in. This allows globbing inside directories
2586 whose names may contain glob-sensitive characters. The returned names
2587 include the directory name unless +'-tails'+ is specified.
2589 If +'-tails'+ is specified, along with +-directory+, the returned names
2590 are relative to the given directory.
2595 +*global* 'varName ?varName \...?'+
2597 This command is ignored unless a Tcl procedure is being interpreted.
2598 If so, then it declares each given +'varName'+ to be a global variable
2599 rather than a local one. For the duration of the current procedure
2600 (and only while executing in the current procedure), any reference to
2601 +'varName'+ will be bound to a global variable instead
2604 An alternative to using `global` is to use the +::+ prefix
2605 to explicitly name a variable in the global scope.
2609 +*if* 'expr1' ?*then*? 'body1' *elseif* 'expr2' ?*then*? 'body2' *elseif* \... ?*else*? ?'bodyN'?+
2611 The `if` command evaluates +'expr1'+ as an expression (in the same way
2612 that `expr` evaluates its argument). The value of the expression must
2613 be numeric; if it is non-zero then +'body1'+ is executed by passing it to
2614 the Tcl interpreter.
2616 Otherwise +'expr2'+ is evaluated as an expression and if it is non-zero
2617 then +'body2'+ is executed, and so on.
2619 If none of the expressions evaluates to non-zero then +'bodyN'+ is executed.
2621 The +then+ and +else+ arguments are optional "noise words" to make the
2622 command easier to read.
2624 There may be any number of +elseif+ clauses, including zero. +'bodyN'+
2625 may also be omitted as long as +else+ is omitted too.
2627 The return value from the command is the result of the body script that
2628 was executed, or an empty string if none of the expressions was non-zero
2629 and there was no +'bodyN'+.
2633 +*incr* 'varName ?increment?'+
2635 Increment the value stored in the variable whose name is +'varName'+.
2636 The value of the variable must be integral.
2638 If +'increment'+ is supplied then its value (which must be an
2639 integer) is added to the value of variable +'varName'+; otherwise
2640 1 is added to +'varName'+.
2642 The new value is stored as a decimal string in variable +'varName'+
2643 and also returned as result.
2645 If the variable does not exist, the variable is implicitly created
2646 and set to +0+ first.
2651 +*info* 'option ?arg\...?'+::
2653 Provide information about various internals to the Tcl interpreter.
2654 The legal +'option'+'s (which may be abbreviated) are:
2656 +*info args* 'procname'+::
2657 Returns a list containing the names of the arguments to procedure
2658 +'procname'+, in order. +'procname'+ must be the name of a
2659 Tcl command procedure.
2661 +*info alias* 'command'+::
2662 +'command'+ must be an alias created with `alias`. In which case the target
2663 command and arguments, as passed to `alias` are returned. See `exists -alias`
2665 +*info body* 'procname'+::
2666 Returns the body of procedure +'procname'+. +'procname'+ must be
2667 the name of a Tcl command procedure.
2670 Returns a list of all open file handles from `open` or `socket`
2672 +*info commands* ?'pattern'?+::
2673 If +'pattern'+ isn't specified, returns a list of names of all the
2674 Tcl commands, including both the built-in commands written in C and
2675 the command procedures defined using the `proc` command.
2676 If +'pattern'+ is specified, only those names matching +'pattern'+
2677 are returned. Matching is determined using the same rules as for
2680 +*info complete* 'command' ?'missing'?+::
2681 Returns 1 if +'command'+ is a complete Tcl command in the sense of
2682 having no unclosed quotes, braces, brackets or array element names,
2683 If the command doesn't appear to be complete then 0 is returned.
2684 This command is typically used in line-oriented input environments
2685 to allow users to type in commands that span multiple lines; if the
2686 command isn't complete, the script can delay evaluating it until additional
2687 lines have been typed to complete the command. If +'varName'+ is specified, the
2688 missing character is stored in the variable with that name.
2690 +*info exists* 'varName'+::
2691 Returns '1' if the variable named +'varName'+ exists in the
2692 current context (either as a global or local variable), returns '0'
2695 +*info frame* ?'number'?+::
2696 If +'number'+ is not specified, this command returns a number
2697 which is the same result as `info level` - the current stack frame level.
2698 If +'number'+ is specified, then the result is a list consisting of the procedure,
2699 filename and line number for the procedure call at level +'number'+ on the stack.
2700 If +'number'+ is positive then it selects a particular stack level (1 refers
2701 to the top-most active procedure, 2 to the procedure it called, and
2702 so on); otherwise it gives a level relative to the current level
2703 (0 refers to the current procedure, -1 to its caller, and so on).
2704 The level has an identical meaning to `info level`.
2706 +*info globals* ?'pattern'?+::
2707 If +'pattern'+ isn't specified, returns a list of all the names
2708 of currently-defined global variables.
2709 If +'pattern'+ is specified, only those names matching +'pattern'+
2710 are returned. Matching is determined using the same rules as for
2714 An alias for `os.gethostname` for compatibility with Tcl 6.x
2716 +*info level* ?'number'?+::
2717 If +'number'+ is not specified, this command returns a number
2718 giving the stack level of the invoking procedure, or 0 if the
2719 command is invoked at top-level. If +'number'+ is specified,
2720 then the result is a list consisting of the name and arguments for the
2721 procedure call at level +'number'+ on the stack. If +'number'+
2722 is positive then it selects a particular stack level (1 refers
2723 to the top-most active procedure, 2 to the procedure it called, and
2724 so on); otherwise it gives a level relative to the current level
2725 (0 refers to the current procedure, -1 to its caller, and so on).
2726 See the `uplevel` command for more information on what stack
2729 +*info locals* ?'pattern'?+::
2730 If +'pattern'+ isn't specified, returns a list of all the names
2731 of currently-defined local variables, including arguments to the
2732 current procedure, if any. Variables defined with the `global`
2733 and `upvar` commands will not be returned. If +'pattern'+ is
2734 specified, only those names matching +'pattern'+ are returned.
2735 Matching is determined using the same rules as for `string match`.
2737 +*info nameofexecutable*+::
2738 Returns the name of the binary file from which the application
2739 was invoked. A full path will be returned, unless the path
2740 can't be determined, in which case the empty string will be returned.
2742 +*info procs* ?'pattern'?+::
2743 If +'pattern'+ isn't specified, returns a list of all the
2744 names of Tcl command procedures.
2745 If +'pattern'+ is specified, only those names matching +'pattern'+
2746 are returned. Matching is determined using the same rules as for
2749 +*info references*+::
2750 Returns a list of all references which have not yet been garbage
2753 +*info returncodes* ?'code'?+::
2754 Returns a list representing the mapping of standard return codes
2755 to names. e.g. +{0 ok 1 error 2 return \...}+. If a code is given,
2756 instead returns the name for the given code.
2759 If a Tcl script file is currently being evaluated (i.e. there is a
2760 call to 'Jim_EvalFile' active or there is an active invocation
2761 of the `source` command), then this command returns the name
2762 of the innermost file being processed. Otherwise the command returns an
2765 +*info source* 'script ?filename line?'+::
2766 With a single argument, returns the original source location of the given script as a list of
2767 +{filename linenumber}+. If the source location can't be determined, the
2768 list +{{} 0}+ is returned. If +'filename'+ and +'line'+ are given, returns a copy
2769 of +'script'+ with the associate source information. This can be useful to produce
2770 useful messages from `eval`, etc. if the original source information may be lost.
2772 +*info stacktrace*+::
2773 After an error is caught with `catch`, returns the stack trace as a list
2774 of +{procedure filename line \...}+.
2776 +*info statics* 'procname'+::
2777 Returns a dictionary of the static variables of procedure
2778 +'procname'+. +'procname'+ must be the name of a Tcl command
2779 procedure. An empty dictionary is returned if the procedure has
2780 no static variables.
2783 Returns the version number for this version of Jim in the form +*x.yy*+.
2785 +*info vars* ?'pattern'?+::
2786 If +'pattern'+ isn't specified,
2787 returns a list of all the names of currently-visible variables, including
2788 both locals and currently-visible globals.
2789 If +'pattern'+ is specified, only those names matching +'pattern'+
2790 are returned. Matching is determined using the same rules as for
2795 +*join* 'list ?joinString?'+
2797 The +'list'+ argument must be a valid Tcl list. This command returns the
2798 string formed by joining all of the elements of +'list'+ together with
2799 +'joinString'+ separating each adjacent pair of elements.
2801 The +'joinString'+ argument defaults to a space character.
2805 +*kill* ?'SIG'|*-0*? 'pid'+
2807 Sends the given signal to the process identified by +'pid'+.
2809 The signal may be specified by name or number in one of the following forms:
2817 The signal name may be in either upper or lower case.
2819 The special signal name +-0+ simply checks that a signal +'could'+ be sent.
2821 If no signal is specified, SIGTERM is used.
2823 An error is raised if the signal could not be delivered.
2827 +*lambda* 'args ?statics? body'+
2829 The `lambda` command is identical to `proc`, except rather than
2830 creating a named procedure, it creates an anonymous procedure and returns
2831 the name of the procedure.
2833 See `proc` and GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
2837 +*lappend* 'varName value ?value value \...?'+
2839 Treat the variable given by +'varName'+ as a list and append each of
2840 the +'value'+ arguments to that list as a separate element, with spaces
2843 If +'varName'+ doesn't exist, it is created as a list with elements given
2844 by the +'value'+ arguments. `lappend` is similar to `append` except that
2845 each +'value'+ is appended as a list element rather than raw text.
2847 This command provides a relatively efficient way to build up large lists.
2852 is much more efficient than
2854 set a [concat $a [list $b]]
2860 +*lassign* 'list varName ?varName \...?'+
2862 This command treats the value +'list'+ as a list and assigns successive elements from that list to
2863 the variables given by the +'varName'+ arguments in order. If there are more variable names than
2864 list elements, the remaining variables are set to the empty string. If there are more list elements
2865 than variables, a list of unassigned elements is returned.
2867 jim> lassign {1 2 3} a b; puts a=$a,b=$b
2873 +*local* 'cmd ?arg\...?'+
2875 First, `local` evaluates +'cmd'+ with the given arguments. The return value must
2876 be the name of an existing command, which is marked as having local scope.
2877 This means that when the current procedure exits, the specified
2878 command is deleted. This can be useful with `lambda`, local procedures or
2879 to automatically close a filehandle.
2881 In addition, if a command already exists with the same name,
2882 the existing command will be kept rather than deleted, and may be called
2883 via `upcall`. The previous command will be restored when the current
2884 procedure exits. See `upcall` for more details.
2886 In this example, a local procedure is created. Note that the procedure
2887 continues to have global scope while it is active.
2890 # proc ... returns "inner" which is marked local
2891 local proc inner {} {
2892 # will be deleted when 'outer' exits
2899 In this example, the lambda is deleted at the end of the procedure rather
2900 than waiting until garbage collection.
2903 set x [lambda inner {args} {
2904 # will be deleted when 'outer' exits
2906 # Use 'function' here which simply returns $x
2915 +*loop* 'var first limit ?incr? body'+
2917 Similar to `for` except simpler and possibly more efficient.
2918 With a positive increment, equivalent to:
2920 for {set var $first} {$var < $limit} {incr var $incr} $body
2922 If +'incr'+ is not specified, 1 is used.
2923 Note that setting the loop variable inside the loop does not
2924 affect the loop count.
2928 +*lindex* 'list ?index ...?'+
2930 Treats +'list'+ as a Tcl list and returns element +'index'+ from it
2931 (0 refers to the first element of the list).
2932 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
2934 In extracting the element, +'lindex'+ observes the same rules concerning
2935 braces and quotes and backslashes as the Tcl command interpreter; however,
2936 variable substitution and command substitution do not occur.
2938 If no index values are given, simply returns +'list'+
2940 If +'index'+ is negative or greater than or equal to the number of elements
2941 in +'list'+, then an empty string is returned.
2943 If additional index arguments are supplied, then each argument is
2944 used in turn to select an element from the previous indexing
2945 operation, allowing the script to select elements from sublists.
2949 +*linsert* 'list index element ?element element \...?'+
2951 This command produces a new list from +'list'+ by inserting all
2952 of the +'element'+ arguments just before the element +'index'+
2953 of +'list'+. Each +'element'+ argument will become
2954 a separate element of the new list. If +'index'+ is less than
2955 or equal to zero, then the new elements are inserted at the
2956 beginning of the list. If +'index'+ is greater than or equal
2957 to the number of elements in the list, then the new elements are
2958 appended to the list.
2960 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
2965 +*list* 'arg ?arg \...?'+
2967 This command returns a list comprised of all the arguments, +'arg'+. Braces
2968 and backslashes get added as necessary, so that the `lindex` command
2969 may be used on the result to re-extract the original arguments, and also
2970 so that `eval` may be used to execute the resulting list, with
2971 +'arg1'+ comprising the command's name and the other args comprising
2972 its arguments. `list` produces slightly different results than
2973 `concat`: `concat` removes one level of grouping before forming
2974 the list, while `list` works directly from the original arguments.
2975 For example, the command
2977 list a b {c d e} {f {g h}}
2981 a b {c d e} {f {g h}}
2983 while `concat` with the same arguments will return
2991 Treats +'list'+ as a list and returns a decimal string giving
2992 the number of elements in it.
2996 +*lset* 'varName ?index ..? newValue'+
2998 Sets an element in a list.
3000 The `lset` command accepts a parameter, +'varName'+, which it interprets
3001 as the name of a variable containing a Tcl list. It also accepts
3002 zero or more indices into the list. Finally, it accepts a new value
3003 for an element of varName. If no indices are presented, the command
3006 lset varName newValue
3008 In this case, newValue replaces the old value of the variable
3011 When presented with a single index, the `lset` command
3012 treats the content of the varName variable as a Tcl list. It addresses
3013 the index'th element in it (0 refers to the first element of the
3014 list). When interpreting the list, `lset` observes the same rules
3015 concerning braces and quotes and backslashes as the Tcl command
3016 interpreter; however, variable substitution and command substitution
3017 do not occur. The command constructs a new list in which the
3018 designated element is replaced with newValue. This new list is
3019 stored in the variable varName, and is also the return value from
3022 If index is negative or greater than or equal to the number of
3023 elements in $varName, then an error occurs.
3025 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'index'+.
3027 If additional index arguments are supplied, then each argument is
3028 used in turn to address an element within a sublist designated by
3029 the previous indexing operation, allowing the script to alter
3030 elements in sublists. The command,
3034 replaces element 2 of sublist 1 with +'newValue'+.
3036 The integer appearing in each index argument must be greater than
3037 or equal to zero. The integer appearing in each index argument must
3038 be strictly less than the length of the corresponding list. In other
3039 words, the `lset` command cannot change the size of a list. If an
3040 index is outside the permitted range, an error is reported.
3045 +*lmap* 'varName list body'+
3047 +*lmap* 'varList list ?varList2 list2 \...? body'+
3049 `lmap` is a "collecting" `foreach` which returns a list of its results.
3053 jim> lmap i {1 2 3 4 5} {expr $i*$i}
3055 jim> lmap a {1 2 3} b {A B C} {list $a $b}
3058 If the body invokes `continue`, no value is added for this iteration.
3059 If the body invokes `break`, the loop ends and no more values are added.
3065 Loads the dynamic extension, +'filename'+. Generally the filename should have
3066 the extension +.so+. The initialisation function for the module must be based
3067 on the name of the file. For example loading +hwaccess.so+ will invoke
3068 the initialisation function, +Jim_hwaccessInit+. Normally the `load` command
3069 should not be used directly. Instead it is invoked automatically by `package require`.
3073 +*lrange* 'list first last'+
3075 +'list'+ must be a valid Tcl list. This command will return a new
3076 list consisting of elements +'first'+ through +'last'+, inclusive.
3078 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
3080 If +'last'+ is greater than or equal to the number of elements
3081 in the list, then it is treated as if it were +end+.
3083 If +'first'+ is greater than +'last'+ then an empty string
3086 Note: +"`lrange` 'list first first'"+ does not always produce the
3087 same result as +"`lindex` 'list first'"+ (although it often does
3088 for simple fields that aren't enclosed in braces); it does, however,
3089 produce exactly the same results as +"`list` [`lindex` 'list first']"+
3094 +*lreplace* 'list first last ?element element \...?'+
3096 Returns a new list formed by replacing one or more elements of
3097 +'list'+ with the +'element'+ arguments.
3099 +'first'+ gives the index in +'list'+ of the first element
3102 If +'first'+ is less than zero then it refers to the first
3103 element of +'list'+; the element indicated by +'first'+
3104 must exist in the list.
3106 +'last'+ gives the index in +'list'+ of the last element
3107 to be replaced; it must be greater than or equal to +'first'+.
3109 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
3111 The +'element'+ arguments specify zero or more new arguments to
3112 be added to the list in place of those that were deleted.
3114 Each +'element'+ argument will become a separate element of
3117 If no +'element'+ arguments are specified, then the elements
3118 between +'first'+ and +'last'+ are simply deleted.
3122 +*lrepeat* 'number element1 ?element2 \...?'+
3124 Build a list by repeating elements +'number'+ times (which must be
3125 a positive integer).
3134 Returns the list in reverse order.
3136 jim> lreverse {1 2 3}
3141 +*lsearch* '?options? list pattern'+
3143 This command searches the elements +'list'+ to see if one of them matches +'pattern'+. If so, the
3144 command returns the index of the first matching element (unless the options +-all+, +-inline+ or +-bool+ are
3145 specified.) If not, the command returns -1. The option arguments indicates how the elements of
3146 the list are to be matched against pattern and must have one of the values below:
3148 *Note* that this command is different from Tcl in that default match type is +-exact+ rather than +-glob+.
3151 +'pattern'+ is a literal string that is compared for exact equality against each list element.
3152 This is the default.
3155 +'pattern'+ is a glob-style pattern which is matched against each list element using the same
3156 rules as the string match command.
3159 +'pattern'+ is treated as a regular expression and matched against each list element using
3160 the rules described by `regexp`.
3162 +*-command* 'cmdname'+::
3163 +'cmdname'+ is a command which is used to match the pattern against each element of the
3164 list. It is invoked as +'cmdname' ?*-nocase*? 'pattern listvalue'+ and should return 1
3165 for a match, or 0 for no match.
3168 Changes the result to be the list of all matching indices (or all matching values if
3169 +-inline+ is specified as well). If indices are returned, the indices will be in numeric
3170 order. If values are returned, the order of the values will be the order of those values
3171 within the input list.
3174 The matching value is returned instead of its index (or an empty string if no value
3175 matches). If +-all+ is also specified, then the result of the command is the list of all
3176 values that matched. The +-inline+ and +-bool+ options are mutually exclusive.
3179 Changes the result to '1' if a match was found, or '0' otherwise. If +-all+ is also specified,
3180 the result will be a list of '0' and '1' for each element of the list depending upon whether
3181 the corresponding element matches. The +-inline+ and +-bool+ options are mutually exclusive.
3184 This negates the sense of the match, returning the index (or value
3185 if +-inline+ is specified) of the first non-matching value in the
3186 list. If +-bool+ is also specified, the '0' will be returned if a
3187 match is found, or '1' otherwise. If +-all+ is also specified,
3188 non-matches will be returned rather than matches.
3191 Causes comparisons to be handled in a case-insensitive manner.
3195 +*lsort* ?*-index* 'listindex'? ?*-nocase|-integer|-real|-command* 'cmdname'? ?*-unique*? ?*-decreasing*|*-increasing*? 'list'+
3197 Sort the elements of +'list'+, returning a new list in sorted order.
3198 By default, ASCII (or UTF-8) sorting is used, with the result in increasing order.
3200 If +-nocase+ is specified, comparisons are case-insensitive.
3202 If +-integer+ is specified, numeric sorting is used.
3204 If +-real+ is specified, floating point number sorting is used.
3206 If +-command 'cmdname'+ is specified, +'cmdname'+ is treated as a command
3207 name. For each comparison, +'cmdname $value1 $value2+' is called which
3208 should compare the values and return an integer less than, equal
3209 to, or greater than zero if the +'$value1'+ is to be considered less
3210 than, equal to, or greater than +'$value2'+, respectively.
3212 If +-decreasing+ is specified, the resulting list is in the opposite
3213 order to what it would be otherwise. +-increasing+ is the default.
3215 If +-unique+ is specified, then only the last set of duplicate elements found in the list will be retained.
3216 Note that duplicates are determined relative to the comparison used in the sort. Thus if +-index 0+ is used,
3217 +{1 a}+ and +{1 b}+ would be considered duplicates and only the second element, +{1 b}+, would be retained.
3219 If +-index 'listindex'+ is specified, each element of the list is treated as a list and
3220 the given index is extracted from the list for comparison. The list index may
3221 be any valid list index, such as +1+, +end+ or +end-2+.
3225 +*open* 'fileName ?access?'+
3227 +*open* '|command-pipeline ?access?'+
3229 Opens a file and returns an identifier
3230 that may be used in future invocations
3231 of commands like `read`, `puts`, and `close`.
3232 +'fileName'+ gives the name of the file to open.
3234 The +'access'+ argument indicates the way in which the file is to be accessed.
3235 It may have any of the following values:
3238 Open the file for reading only; the file must already exist.
3241 Open the file for both reading and writing; the file must
3245 Open the file for writing only. Truncate it if it exists. If it doesn't
3246 exist, create a new file.
3249 Open the file for reading and writing. Truncate it if it exists.
3250 If it doesn't exist, create a new file.
3253 Open the file for writing only. The file must already exist, and the file
3254 is positioned so that new data is appended to the file.
3257 Open the file for reading and writing. If the file doesn't
3258 exist, create a new empty file. Set the initial access position
3259 to the end of the file.
3261 +'access'+ defaults to 'r'.
3263 If a file is opened for both reading and writing, then `seek`
3264 must be invoked between a read and a write, or vice versa.
3266 If the first character of +'fileName'+ is "|" then the remaining
3267 characters of +'fileName'+ are treated as a list of arguments that
3268 describe a command pipeline to invoke, in the same style as the
3269 arguments for exec. In this case, the channel identifier returned
3270 by open may be used to write to the command's input pipe or read
3271 from its output pipe, depending on the value of +'access'+. If write-only
3272 access is used (e.g. +'access'+ is 'w'), then standard output for the
3273 pipeline is directed to the current standard output unless overridden
3274 by the command. If read-only access is used (e.g. +'access'+ is r),
3275 standard input for the pipeline is taken from the current standard
3276 input unless overridden by the command.
3278 The `pid` command may be used to return the process ids of the commands
3279 forming the command pipeline.
3281 See also `socket`, `pid`, `exec`
3285 +*package provide* 'name ?version?'+
3287 Indicates that the current script provides the package named +'name'+.
3288 If no version is specified, '1.0' is used.
3290 Any script which provides a package may include this statement
3291 as the first statement, although it is not required.
3293 +*package require* 'name ?version?'*+
3295 Searches for the package with the given +'name'+ by examining each path
3296 in '$::auto_path' and trying to load '$path/$name.so' as a dynamic extension,
3297 or '$path/$name.tcl' as a script package.
3299 The first such file which is found is considered to provide the package.
3300 (The version number is ignored).
3302 If '$name.so' exists, it is loaded with the `load` command,
3303 otherwise if '$name.tcl' exists it is loaded with the `source` command.
3305 If `load` or `source` fails, `package require` will fail immediately.
3306 No further attempt will be made to locate the file.
3314 The first form returns the process identifier of the current process.
3316 The second form accepts a handle returned by `open` and returns a list
3317 of the process ids forming the pipeline in the same form as `exec ... &`.
3318 If 'fileId' represents a regular file handle rather than a command pipeline,
3319 the empty string is returned instead.
3321 See also `open`, `exec`
3325 +*proc* 'name args ?statics? body'+
3327 The `proc` command creates a new Tcl command procedure, +'name'+.
3328 When the new command is invoked, the contents of +'body'+ will be executed.
3329 Tcl interpreter. +'args'+ specifies the formal arguments to the procedure.
3330 If specified, +'statics'+, declares static variables which are bound to the
3333 See PROCEDURES for detailed information about Tcl procedures.
3335 The `proc` command returns +'name'+ (which is useful with `local`).
3337 When a procedure is invoked, the procedure's return value is the
3338 value specified in a `return` command. If the procedure doesn't
3339 execute an explicit `return`, then its return value is the value
3340 of the last command executed in the procedure's body.
3342 If an error occurs while executing the procedure body, then the
3343 procedure-as-a-whole will return that same error.
3347 +*puts* ?*-nonewline*? '?fileId? string'+
3349 +'fileId' *puts* ?*-nonewline*? 'string'+
3351 Writes the characters given by +'string'+ to the file given
3352 by +'fileId'+. +'fileId'+ must have been the return
3353 value from a previous call to `open`, or it may be
3354 +stdout+ or +stderr+ to refer to one of the standard I/O
3355 channels; it must refer to a file that was opened for
3358 In the first form, if no +'fileId'+ is specified then it defaults to +stdout+.
3359 `puts` normally outputs a newline character after +'string'+,
3360 but this feature may be suppressed by specifying the +-nonewline+
3363 Output to files is buffered internally by Tcl; the `flush`
3364 command may be used to force buffered characters to be output.
3370 Returns the path name of the current working directory.
3374 +*rand* '?min? ?max?'+
3376 Returns a random integer between +'min'+ (defaults to 0) and +'max'+
3377 (defaults to the maximum integer).
3379 If only one argument is given, it is interpreted as +'max'+.
3383 +*range* '?start? end ?step?'+
3385 Returns a list of integers starting at +'start'+ (defaults to 0)
3386 and ranging up to but not including +'end'+ in steps of +'step'+ defaults to 1).
3399 +*read* ?*-nonewline*? 'fileId'+
3401 +'fileId' *read* ?*-nonewline*?+
3403 +*read* 'fileId numBytes'+
3405 +'fileId' *read* 'numBytes'+
3408 In the first form, all of the remaining bytes are read from the file
3409 given by +'fileId'+; they are returned as the result of the command.
3410 If the +-nonewline+ switch is specified then the last
3411 character of the file is discarded if it is a newline.
3413 In the second form, the extra argument specifies how many bytes to read;
3414 exactly this many bytes will be read and returned, unless there are fewer than
3415 +'numBytes'+ bytes left in the file; in this case, all the remaining
3418 +'fileId'+ must be +stdin+ or the return value from a previous call
3419 to `open`; it must refer to a file that was opened for reading.
3423 +*regexp ?-nocase? ?-line? ?-indices? ?-start* 'offset'? *?-all? ?-inline? ?--?* 'exp string ?matchVar? ?subMatchVar subMatchVar \...?'+
3425 Determines whether the regular expression +'exp'+ matches part or
3426 all of +'string'+ and returns 1 if it does, 0 if it doesn't.
3428 See REGULAR EXPRESSIONS above for complete information on the
3429 syntax of +'exp'+ and how it is matched against +'string'+.
3431 If additional arguments are specified after +'string'+ then they
3432 are treated as the names of variables to use to return
3433 information about which part(s) of +'string'+ matched +'exp'+.
3434 +'matchVar'+ will be set to the range of +'string'+ that
3435 matched all of +'exp'+. The first +'subMatchVar'+ will contain
3436 the characters in +'string'+ that matched the leftmost parenthesized
3437 subexpression within +'exp'+, the next +'subMatchVar'+ will
3438 contain the characters that matched the next parenthesized
3439 subexpression to the right in +'exp'+, and so on.
3441 Normally, +'matchVar'+ and the each +'subMatchVar'+ are set to hold the
3442 matching characters from `string`, however see +-indices+ and
3445 If there are more values for +'subMatchVar'+ than parenthesized subexpressions
3446 within +'exp'+, or if a particular subexpression in +'exp'+ doesn't
3447 match the string (e.g. because it was in a portion of the expression
3448 that wasn't matched), then the corresponding +'subMatchVar'+ will be
3449 set to +"-1 -1"+ if +-indices+ has been specified or to an empty
3452 The following switches modify the behaviour of +'regexp'+
3455 Causes upper-case and lower-case characters to be treated as
3456 identical during the matching process.
3459 Use newline-sensitive matching. By default, newline
3460 is a completely ordinary character with no special meaning in
3461 either REs or strings. With this flag, +[^+ bracket expressions
3462 and +.+ never match newline, an +^+ anchor matches the null
3463 string after any newline in the string in addition to its normal
3464 function, and the +$+ anchor matches the null string before any
3465 newline in the string in addition to its normal function.
3468 Changes what is stored in the subMatchVars. Instead of
3469 storing the matching characters from string, each variable
3470 will contain a list of two decimal strings giving the indices
3471 in string of the first and last characters in the matching
3472 range of characters.
3474 +*-start* 'offset'+::
3475 Specifies a character index offset into the string at which to start
3476 matching the regular expression. If +-indices+ is
3477 specified, the indices will be indexed starting from the
3478 absolute beginning of the input string. +'offset'+ will be
3479 constrained to the bounds of the input string.
3482 Causes the regular expression to be matched as many times as possible
3483 in the string, returning the total number of matches found. If this
3484 is specified with match variables, they will contain information
3485 for the last match only.
3488 Causes the command to return, as a list, the data that would otherwise
3489 be placed in match variables. When using +-inline+, match variables
3490 may not be specified. If used with +-all+, the list will be concatenated
3491 at each iteration, such that a flat list is always returned. For
3492 each match iteration, the command will append the overall match
3493 data, plus one element for each subexpression in the regular
3497 Marks the end of switches. The argument following this one will be
3498 treated as +'exp'+ even if it starts with a +-+.
3502 +*regsub ?-nocase? ?-all? ?-line? ?-start* 'offset'? ?*--*? 'exp string subSpec ?varName?'+
3504 This command matches the regular expression +'exp'+ against
3505 +'string'+ using the rules described in REGULAR EXPRESSIONS
3508 If +'varName'+ is specified, the commands stores +'string'+ to +'varName'+
3509 with the substitutions detailed below, and returns the number of
3510 substitutions made (normally 1 unless +-all+ is specified).
3511 This is 0 if there were no matches.
3513 If +'varName'+ is not specified, the substituted string will be returned
3516 When copying +'string'+, the portion of +'string'+ that
3517 matched +'exp'+ is replaced with +'subSpec'+.
3518 If +'subSpec'+ contains a +&+ or +{backslash}0+, then it is replaced
3519 in the substitution with the portion of +'string'+ that
3522 If +'subSpec'+ contains a +{backslash}n+, where +'n'+ is a digit
3523 between 1 and 9, then it is replaced in the substitution with
3524 the portion of +'string'+ that matched the +'n'+\'-th
3525 parenthesized subexpression of +'exp'+.
3526 Additional backslashes may be used in +'subSpec'+ to prevent special
3527 interpretation of +&+ or +{backslash}0+ or +{backslash}n+ or
3530 The use of backslashes in +'subSpec'+ tends to interact badly
3531 with the Tcl parser's use of backslashes, so it's generally
3532 safest to enclose +'subSpec'+ in braces if it includes
3535 The following switches modify the behaviour of +'regsub'+
3538 Upper-case characters in +'string'+ are converted to lower-case
3539 before matching against +'exp'+; however, substitutions
3540 specified by +'subSpec'+ use the original unconverted form
3544 All ranges in +'string'+ that match +'exp'+ are found and substitution
3545 is performed for each of these ranges, rather than only the
3546 first. The +&+ and +{backslash}n+ sequences are handled for
3547 each substitution using the information from the corresponding
3551 Use newline-sensitive matching. By default, newline
3552 is a completely ordinary character with no special meaning in
3553 either REs or strings. With this flag, +[^+ bracket expressions
3554 and +.+ never match newline, an +^+ anchor matches the null
3555 string after any newline in the string in addition to its normal
3556 function, and the +$+ anchor matches the null string before any
3557 newline in the string in addition to its normal function.
3559 +*-start* 'offset'+::
3560 Specifies a character index offset into the string at which to
3561 start matching the regular expression. +'offset'+ will be
3562 constrained to the bounds of the input string.
3565 Marks the end of switches. The argument following this one will be
3566 treated as +'exp'+ even if it starts with a +-+.
3570 +*ref* 'string tag ?finalizer?'+
3572 Create a new reference containing +'string'+ of type +'tag'+.
3573 If +'finalizer'+ is specified, it is a command which will be invoked
3574 when the a garbage collection cycle runs and this reference is
3575 no longer accessible.
3577 The finalizer is invoked as:
3579 finalizer reference string
3581 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
3585 +*rename* 'oldName newName'+
3587 Rename the command that used to be called +'oldName'+ so that it
3588 is now called +'newName'+. If +'newName'+ is an empty string
3589 (e.g. {}) then +'oldName'+ is deleted. The `rename` command
3590 returns an empty string as result.
3594 +*return* ?*-code* 'code'? ?*-errorinfo* 'stacktrace'? ?*-errorcode* 'errorcode'? ?*-level* 'n'? ?'value'?+
3596 Return immediately from the current procedure (or top-level command
3597 or `source` command), with +'value'+ as the return value. If +'value'+
3598 is not specified, an empty string will be returned as result.
3600 If +-code+ is specified (as either a number or ok, error, break,
3601 continue, signal, return or exit), this code will be used instead
3602 of +JIM_OK+. This is generally useful when implementing flow of control
3605 If +-level+ is specified and greater than 1, it has the effect of delaying
3606 the new return code from +-code+. This is useful when rethrowing an error
3607 from `catch`. See the implementation of try/catch in tclcompat.tcl for
3608 an example of how this is done.
3610 Note: The following options are only used when +-code+ is JIM_ERR.
3612 If +-errorinfo+ is specified (as returned from `info stacktrace`)
3613 it is used to initialize the stacktrace.
3615 If +-errorcode+ is specified, it is used to set the global variable $::errorCode.
3619 +*scan* 'string format varName1 ?varName2 \...?'+
3621 This command parses fields from an input string in the same fashion
3622 as the C 'sscanf' procedure. +'string'+ gives the input to be parsed
3623 and +'format'+ indicates how to parse it, using '%' fields as in
3624 'sscanf'. All of the 'sscanf' options are valid; see the 'sscanf'
3625 man page for details. Each +'varName'+ gives the name of a variable;
3626 when a field is scanned from +'string'+, the result is converted back
3627 into a string and assigned to the corresponding +'varName'+. The
3628 only unusual conversion is for '%c'. For '%c' conversions a single
3629 character value is converted to a decimal string, which is then
3630 assigned to the corresponding +'varName'+; no field width may be
3631 specified for this conversion.
3635 +*seek* 'fileId offset ?origin?'+
3637 +'fileId' *seek* 'offset ?origin?'+
3639 Change the current access position for +'fileId'+.
3640 The +'offset'+ and +'origin'+ arguments specify the position at
3641 which the next read or write will occur for +'fileId'+.
3642 +'offset'+ must be a number (which may be negative) and +'origin'+
3643 must be one of the following:
3646 The new access position will be +'offset'+ bytes from the start
3650 The new access position will be +'offset'+ bytes from the current
3651 access position; a negative +'offset'+ moves the access position
3652 backwards in the file.
3655 The new access position will be +'offset'+ bytes from the end of
3656 the file. A negative +'offset'+ places the access position before
3657 the end-of-file, and a positive +'offset'+ places the access position
3658 after the end-of-file.
3660 The +'origin'+ argument defaults to +start+.
3662 +'fileId'+ must have been the return value from a previous call to
3663 `open`, or it may be +stdin+, +stdout+, or +stderr+ to refer to one
3664 of the standard I/O channels.
3666 This command returns an empty string.
3670 +*set* 'varName ?value?'+
3672 Returns the value of variable +'varName'+.
3674 If +'value'+ is specified, then set the value of +'varName'+ to +'value'+,
3675 creating a new variable if one doesn't already exist, and return
3678 If +'varName'+ contains an open parenthesis and ends with a
3679 close parenthesis, then it refers to an array element: the characters
3680 before the open parenthesis are the name of the array, and the characters
3681 between the parentheses are the index within the array.
3682 Otherwise +'varName'+ refers to a scalar variable.
3684 If no procedure is active, then +'varName'+ refers to a global
3687 If a procedure is active, then +'varName'+ refers to a parameter
3688 or local variable of the procedure, unless the +'global'+ command
3689 has been invoked to declare +'varName'+ to be global.
3691 The +::+ prefix may also be used to explicitly reference a variable
3692 in the global scope.
3696 +*setref* 'reference string'+
3698 Store a new string in +'reference'+, replacing the existing string.
3699 The reference must be a valid reference create with the `ref`
3702 See GARBAGE COLLECTION, REFERENCES, LAMBDA FUNCTION for more detail.
3706 Command for signal handling.
3708 See `kill` for the different forms which may be used to specify signals.
3710 Commands which return a list of signal names do so using the canonical form:
3713 +*signal handle* ?'signals \...'?+::
3714 If no signals are given, returns a list of all signals which are currently
3716 If signals are specified, these are added to the list of signals currently
3719 +*signal ignore* ?'signals \...'?+::
3720 If no signals are given, returns a lists all signals which are currently
3722 If signals are specified, these are added to the list of signals
3723 currently being ignored. These signals are still delivered, but
3724 are not considered by `catch -signal` or `try -signal`. Use
3725 `signal check` to determine which signals have occurred but
3728 +*signal default* ?'signals \...'?+::
3729 If no signals are given, returns a lists all signals which are currently have
3730 the default behaviour.
3731 If signals are specified, these are added to the list of signals which have
3732 the default behaviour.
3734 +*signal check ?-clear?* ?'signals \...'?+::
3735 Returns a list of signals which have been delivered to the process
3736 but are 'ignored'. If signals are specified, only that set of signals will
3737 be checked, otherwise all signals will be checked.
3738 If +-clear+ is specified, any signals returned are removed and will not be
3739 returned by subsequent calls to `signal check` unless delivered again.
3741 +*signal throw* ?'signal'?+::
3742 Raises the given signal, which defaults to +SIGINT+ if not specified.
3743 The behaviour is identical to:
3747 Note that `signal handle` and `signal ignore` represent two forms of signal
3748 handling. `signal handle` is used in conjunction with `catch -signal` or `try -signal`
3749 to immediately abort execution when the signal is delivered. Alternatively, `signal ignore`
3750 is used in conjunction with `signal check` to handle signal synchronously. Consider the
3753 Prevent a processing from taking too long
3755 signal handle SIGALRM
3758 .. possibly long running process ..
3761 puts stderr "Process took too long"
3764 Handle SIGHUP to reconfigure:
3766 signal ignore SIGHUP
3768 ... handle configuration/reconfiguration ...
3769 while {[signal check -clear SIGHUP] eq ""} {
3770 ... do processing ..
3772 # Received SIGHUP, so reconfigure
3779 Pauses for the given number of seconds, which may be a floating
3780 point value less than one to sleep for less than a second, or an
3781 integer to sleep for one or more seconds.
3785 +*source* 'fileName'+
3787 Read file +'fileName'+ and pass the contents to the Tcl interpreter
3788 as a sequence of commands to execute in the normal fashion. The return
3789 value of `source` is the return value of the last command executed
3790 from the file. If an error occurs in executing the contents of the
3791 file, then the `source` command will return that error.
3793 If a `return` command is invoked from within the file, the remainder of
3794 the file will be skipped and the `source` command will return
3795 normally with the result from the `return` command.
3799 +*split* 'string ?splitChars?'+
3801 Returns a list created by splitting +'string'+ at each character
3802 that is in the +'splitChars'+ argument.
3804 Each element of the result list will consist of the
3805 characters from +'string'+ between instances of the
3806 characters in +'splitChars'+.
3808 Empty list elements will be generated if +'string'+ contains
3809 adjacent characters in +'splitChars'+, or if the first or last
3810 character of +'string'+ is in +'splitChars'+.
3812 If +'splitChars'+ is an empty string then each character of
3813 +'string'+ becomes a separate element of the result list.
3815 +'splitChars'+ defaults to the standard white-space characters.
3818 split "comp.unix.misc" .
3820 returns +'"comp unix misc"'+ and
3822 split "Hello world" {}
3824 returns +'"H e l l o { } w o r l d"'+.
3829 +*stackdump* 'stacktrace'+
3831 Creates a human readable representation of a stack trace.
3838 Returns a live stack trace as a list of +proc file line proc file line \...+.
3839 Iteratively uses `info frame` to create the stack trace. This stack trace is in the
3840 same form as produced by `catch` and `info stacktrace`
3842 See also `stackdump`.
3847 +*string* 'option arg ?arg \...?'+
3849 Perform one of several string operations, depending on +'option'+.
3850 The legal options (which may be abbreviated) are:
3852 +*string bytelength* 'string'+::
3853 Returns the length of the string in bytes. This will return
3854 the same value as `string length` if UTF-8 support is not enabled,
3855 or if the string is composed entirely of ASCII characters.
3856 See UTF-8 AND UNICODE.
3858 +*string byterange* 'string first last'+::
3859 Like `string range` except works on bytes rather than characters.
3860 These commands are identical if UTF-8 support is not enabled.
3862 +*string cat* '?string1 string2 \...?'+::
3863 Concatenates the given strings into a single string.
3865 +*string compare ?-nocase?* ?*-length* 'len? string1 string2'+::
3866 Perform a character-by-character comparison of strings +'string1'+ and
3867 +'string2'+ in the same way as the C 'strcmp' procedure. Return
3868 -1, 0, or 1, depending on whether +'string1'+ is lexicographically
3869 less than, equal to, or greater than +'string2'+. If +-length+
3870 is specified, then only the first +'len'+ characters are used
3871 in the comparison. If +'len'+ is negative, it is ignored.
3872 Performs a case-insensitive comparison if +-nocase+ is specified.
3874 +*string equal ?-nocase?* '?*-length* len?' 'string1 string2'+::
3875 Returns 1 if the strings are equal, or 0 otherwise. If +-length+
3876 is specified, then only the first +'len'+ characters are used
3877 in the comparison. If +'len'+ is negative, it is ignored.
3878 Performs a case-insensitive comparison if +-nocase+ is specified.
3880 +*string first* 'string1 string2 ?firstIndex?'+::
3881 Search +'string2'+ for a sequence of characters that exactly match
3882 the characters in +'string1'+. If found, return the index of the
3883 first character in the first such match within +'string2'+. If not
3884 found, return -1. If +'firstIndex'+ is specified, matching will start
3885 from +'firstIndex'+ of +'string1'+.
3887 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'firstIndex'+.
3889 +*string index* 'string charIndex'+::
3890 Returns the +'charIndex'+'th character of the +'string'+
3891 argument. A +'charIndex'+ of 0 corresponds to the first
3892 character of the string.
3893 If +'charIndex'+ is less than 0 or greater than
3894 or equal to the length of the string then an empty string is
3897 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'charIndex'+.
3899 +*string is* 'class' ?*-strict*? 'string'+::
3900 Returns 1 if +'string'+ is a valid member of the specified character
3901 class, otherwise returns 0. If +-strict+ is specified, then an
3902 empty string returns 0, otherwise an empty string will return 1
3903 on any class. The following character classes are recognized
3904 (the class name can be abbreviated):
3906 +alnum+;; Any alphabet or digit character.
3907 +alpha+;; Any alphabet character.
3908 +ascii+;; Any character with a value less than 128 (those that are in the 7-bit ascii range).
3909 +control+;; Any control character.
3910 +digit+;; Any digit character.
3911 +double+;; Any of the valid forms for a double in Tcl, with optional surrounding whitespace.
3912 In case of under/overflow in the value, 0 is returned.
3913 +graph+;; Any printing character, except space.
3914 +integer+;; Any of the valid string formats for an integer value in Tcl, with optional surrounding whitespace.
3915 +lower+;; Any lower case alphabet character.
3916 +print+;; Any printing character, including space.
3917 +punct+;; Any punctuation character.
3918 +space+;; Any space character.
3919 +upper+;; Any upper case alphabet character.
3920 +xdigit+;; Any hexadecimal digit character ([0-9A-Fa-f]).
3922 Note that string classification does +'not'+ respect UTF-8. See UTF-8 AND UNICODE
3924 +*string last* 'string1 string2 ?lastIndex?'+::
3925 Search +'string2'+ for a sequence of characters that exactly match
3926 the characters in +'string1'+. If found, return the index of the
3927 first character in the last such match within +'string2'+. If there
3928 is no match, then return -1. If +'lastIndex'+ is specified, only characters
3929 up to +'lastIndex'+ of +'string2'+ will be considered in the match.
3931 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'lastIndex'+.
3933 +*string length* 'string'+::
3934 Returns a decimal string giving the number of characters in +'string'+.
3935 If UTF-8 support is enabled, this may be different than the number of bytes.
3936 See UTF-8 AND UNICODE
3938 +*string map ?-nocase?* 'mapping string'+::
3939 Replaces substrings in +'string'+ based on the key-value pairs in
3940 +'mapping'+, which is a list of +key value key value \...+ as in the form
3941 returned by `array get`. Each instance of a key in the string will be
3942 replaced with its corresponding value. If +-nocase+ is specified, then
3943 matching is done without regard to case differences. Both key and value may
3944 be multiple characters. Replacement is done in an ordered manner, so the
3945 key appearing first in the list will be checked first, and so on. +'string'+ is
3946 only iterated over once, so earlier key replacements will have no affect for
3947 later key matches. For example,
3949 string map {abc 1 ab 2 a 3 1 0} 1abcaababcabababc
3952 will return the string +01321221+.
3954 Note that if an earlier key is a prefix of a later one, it will completely mask the later
3955 one. So if the previous example is reordered like this,
3957 string map {1 0 ab 2 a 3 abc 1} 1abcaababcabababc
3960 it will return the string +02c322c222c+.
3962 +*string match ?-nocase?* 'pattern string'+::
3963 See if +'pattern'+ matches +'string'+; return 1 if it does, 0
3964 if it doesn't. Matching is done in a fashion similar to that
3965 used by the C-shell. For the two strings to match, their contents
3966 must be identical except that the following special sequences
3967 may appear in +'pattern'+:
3970 Matches any sequence of characters in +'string'+,
3971 including a null string.
3974 Matches any single character in +'string'+.
3977 Matches any character in the set given by +'chars'+.
3978 If a sequence of the form +'x-y'+ appears in +'chars'+,
3979 then any character between +'x'+ and +'y'+, inclusive,
3983 Matches the single character +'x'+. This provides a way of
3984 avoiding the special interpretation of the characters +{backslash}*?[]+
3987 Performs a case-insensitive comparison if +-nocase+ is specified.
3989 +*string range* 'string first last'+::
3990 Returns a range of consecutive characters from +'string'+, starting
3991 with the character whose index is +'first'+ and ending with the
3992 character whose index is +'last'+. An index of 0 refers to the
3993 first character of the string.
3995 See STRING AND LIST INDEX SPECIFICATIONS for all allowed forms for +'first'+ and +'last'+.
3997 If +'first'+ is less than zero then it is treated as if it were zero, and
3998 if +'last'+ is greater than or equal to the length of the string then
3999 it is treated as if it were +end+. If +'first'+ is greater than
4000 +'last'+ then an empty string is returned.
4002 +*string repeat* 'string count'+::
4003 Returns a new string consisting of +'string'+ repeated +'count'+ times.
4005 +*string replace* 'string first last ?newstring?'+::
4006 Removes a range of consecutive characters from +'string'+, starting
4007 with the character whose index is +'first'+ and ending with the
4008 character whose index is +'last'+. If +'newstring'+ is specified,
4009 then it is placed in the removed character range. If +'first'+ is
4010 less than zero then it is treated as if it were zero, and if +'last'+
4011 is greater than or equal to the length of the string then it is
4012 treated as if it were +end+. If +'first'+ is greater than +'last'+
4013 or the length of the initial string, or +'last'+ is less than 0,
4014 then the initial string is returned untouched.
4016 +*string reverse* 'string'+::
4017 Returns a string that is the same length as +'string'+ but
4018 with its characters in the reverse order.
4020 +*string tolower* 'string'+::
4021 Returns a value equal to +'string'+ except that all upper case
4022 letters have been converted to lower case.
4024 +*string totitle* 'string'+::
4025 Returns a value equal to +'string'+ except that the first character
4026 is converted to title case (or upper case if there is no UTF-8 titlecase variant)
4027 and all remaining characters have been converted to lower case.
4029 +*string toupper* 'string'+::
4030 Returns a value equal to +'string'+ except that all lower case
4031 letters have been converted to upper case.
4033 +*string trim* 'string ?chars?'+::
4034 Returns a value equal to +'string'+ except that any leading
4035 or trailing characters from the set given by +'chars'+ are
4037 If +'chars'+ is not specified then white space is removed
4038 (spaces, tabs, newlines, and carriage returns).
4040 +*string trimleft* 'string ?chars?'+::
4041 Returns a value equal to +'string'+ except that any
4042 leading characters from the set given by +'chars'+ are
4044 If +'chars'+ is not specified then white space is removed
4045 (spaces, tabs, newlines, and carriage returns).
4047 +*string trimright* 'string ?chars?'+::
4048 Returns a value equal to +'string'+ except that any
4049 trailing characters from the set given by +'chars'+ are
4051 If +'chars'+ is not specified then white space is removed
4052 (spaces, tabs, newlines, and carriage returns).
4053 Null characters are always removed.
4057 +*subst ?-nobackslashes? ?-nocommands? ?-novariables?* 'string'+
4059 This command performs variable substitutions, command substitutions,
4060 and backslash substitutions on its string argument and returns the
4061 fully-substituted result. The substitutions are performed in exactly
4062 the same way as for Tcl commands. As a result, the string argument
4063 is actually substituted twice, once by the Tcl parser in the usual
4064 fashion for Tcl commands, and again by the subst command.
4066 If any of the +-nobackslashes+, +-nocommands+, or +-novariables+ are
4067 specified, then the corresponding substitutions are not performed.
4068 For example, if +-nocommands+ is specified, no command substitution
4069 is performed: open and close brackets are treated as ordinary
4070 characters with no special interpretation.
4072 *Note*: when it performs its substitutions, subst does not give any
4073 special treatment to double quotes or curly braces. For example,
4074 the following script returns +xyz \{44\}+, not +xyz \{$a\}+.
4082 +*switch* '?options? string pattern body ?pattern body \...?'+
4084 +*switch* '?options? string {pattern body ?pattern body \...?}'+
4086 The `switch` command matches its string argument against each of
4087 the pattern arguments in order. As soon as it finds a pattern that
4088 matches string it evaluates the following body and returns the
4089 result of that evaluation. If the last pattern argument is default
4090 then it matches anything. If no pattern argument matches string and
4091 no default is given, then the `switch` command returns an empty string.
4092 If the initial arguments to switch start with - then they are treated
4093 as options. The following options are currently supported:
4096 Use exact matching when comparing string to a
4097 pattern. This is the default.
4100 When matching string to the patterns, use glob-style
4101 matching (i.e. the same as implemented by the string
4105 When matching string to the patterns, use regular
4106 expression matching (i.e. the same as implemented
4107 by the regexp command).
4109 +-command 'commandname'+::
4110 When matching string to the patterns, use the given command, which
4111 must be a single word. The command is invoked as
4112 'commandname pattern string', or 'commandname -nocase pattern string'
4113 and must return 1 if matched, or 0 if not.
4116 Marks the end of options. The argument following
4117 this one will be treated as string even if it starts
4120 Two syntaxes are provided for the pattern and body arguments. The
4121 first uses a separate argument for each of the patterns and commands;
4122 this form is convenient if substitutions are desired on some of the
4123 patterns or commands. The second form places all of the patterns
4124 and commands together into a single argument; the argument must
4125 have proper list structure, with the elements of the list being the
4126 patterns and commands. The second form makes it easy to construct
4127 multi-line `switch` commands, since the braces around the whole list
4128 make it unnecessary to include a backslash at the end of each line.
4129 Since the pattern arguments are in braces in the second form, no
4130 command or variable substitutions are performed on them; this makes
4131 the behaviour of the second form different than the first form in
4134 If a body is specified as +-+ it means that the body for the next
4135 pattern should also be used as the body for this pattern (if the
4136 next pattern also has a body of +-+ then the body after that is
4137 used, and so on). This feature makes it possible to share a single
4138 body among several patterns.
4140 Below are some examples of `switch` commands:
4142 switch abc a - b {format 1} abc {format 2} default {format 3}
4146 switch -regexp aaab {
4166 +*tailcall* 'cmd ?arg\...?'+
4168 The `tailcall` command provides an optimised way of invoking a command whilst replacing
4169 the current call frame. This is similar to 'exec' in Bourne Shell.
4171 The following are identical except the first immediately replaces the current call frame.
4175 return [uplevel 1 [list a b c]]
4177 `tailcall` is useful as a dispatch mechanism:
4180 tailcall sub_$cmd {*}$args
4191 Returns a decimal string giving the current access position in
4194 +'fileId'+ must have been the return value from a previous call to
4195 `open`, or it may be +stdin+, +stdout+, or +stderr+ to refer to one
4196 of the standard I/O channels.
4200 +*throw* 'code ?msg?'+
4202 This command throws an exception (return) code along with an optional message.
4203 This command is mostly for convenient usage with `try`.
4205 The command +throw break+ is equivalent to +break+.
4206 The command +throw 20 message+ can be caught with an +on 20 \...+ clause to `try`.
4210 +*time* 'command ?count?'+
4212 This command will call the Tcl interpreter +'count'+
4213 times to execute +'command'+ (or once if +'count'+ isn't
4214 specified). It will then return a string of the form
4216 503 microseconds per iteration
4218 which indicates the average amount of time required per iteration,
4221 Time is measured in elapsed time, not CPU time.
4225 +*try* '?catchopts? tryscript' ?*on* 'returncodes {?resultvar? ?optsvar?} handlerscript \...'? ?*finally* 'finalscript'?+
4227 The `try` command is provided as a convenience for exception handling.
4229 This interpeter first evaluates +'tryscript'+ under the effect of the catch
4230 options +'catchopts'+ (e.g. +-signal -noexit --+, see `catch`).
4232 It then evaluates the script for the first matching 'on' handler
4233 (there many be zero or more) based on the return code from the `try`
4234 section. For example a normal +JIM_ERR+ error will be matched by
4235 an 'on error' handler.
4237 Finally, any +'finalscript'+ is evaluated.
4239 The result of this command is the result of +'tryscript'+, except in the
4240 case where an exception occurs in a matching 'on' handler script or the 'finally' script,
4241 in which case the result is this new exception.
4243 The specified +'returncodes'+ is a list of return codes either as names ('ok', 'error', 'break', etc.)
4246 If +'resultvar'+ and +'optsvar'+ are specified, they are set as for `catch` before evaluating
4247 the matching handler.
4254 } on {continue break} {} {
4255 error "Unexpected break/continue"
4256 } on error {msg opts} {
4257 puts "Dealing with error"
4258 return {*}$opts $msg
4260 puts "Got signal: $sig"
4265 If break, continue or error are raised, they are dealt with by the matching
4268 In any case, the file will be closed via the 'finally' clause.
4270 See also `throw`, `catch`, `return`, `error`.
4274 +*unknown* 'cmdName ?arg arg ...?'+
4276 This command doesn't actually exist as part of Tcl, but Tcl will
4277 invoke it if it does exist.
4279 If the Tcl interpreter encounters a command name for which there
4280 is not a defined command, then Tcl checks for the existence of
4281 a command named `unknown`.
4283 If there is no such command, then the interpreter returns an
4286 If the `unknown` command exists, then it is invoked with
4287 arguments consisting of the fully-substituted name and arguments
4288 for the original non-existent command.
4290 The `unknown` command typically does things like searching
4291 through library directories for a command procedure with the name
4292 +'cmdName'+, or expanding abbreviated command names to full-length,
4293 or automatically executing unknown commands as UNIX sub-processes.
4295 In some cases (such as expanding abbreviations) `unknown` will
4296 change the original command slightly and then (re-)execute it.
4297 The result of the `unknown` command is used as the result for
4298 the original non-existent command.
4302 +*unset ?-nocomplain? ?--?* '?name name ...?'+
4305 Each +'name'+ is a variable name, specified in any of the
4306 ways acceptable to the `set` command.
4308 If a +'name'+ refers to an element of an array, then that
4309 element is removed without affecting the rest of the array.
4311 If a +'name'+ consists of an array name with no parenthesized
4312 index, then the entire array is deleted.
4314 The `unset` command returns an empty string as result.
4316 An error occurs if any of the variables doesn't exist, unless '-nocomplain'
4317 is specified. The '--' argument may be specified to stop option processing
4318 in case the variable name may be '-nocomplain'.
4322 +*upcall* 'command ?args ...?'+
4324 May be used from within a proc defined as `local` `proc` in order to call
4325 the previous, hidden version of the same command.
4327 If there is no previous definition of the command, an error is returned.
4331 +*uplevel* '?level? command ?command ...?'+
4333 All of the +'command'+ arguments are concatenated as if they had
4334 been passed to `concat`; the result is then evaluated in the
4335 variable context indicated by +'level'+. `uplevel` returns
4336 the result of that evaluation. If +'level'+ is an integer, then
4337 it gives a distance (up the procedure calling stack) to move before
4338 executing the command. If +'level'+ consists of +\#+ followed by
4339 a number then the number gives an absolute level number. If +'level'+
4340 is omitted then it defaults to +1+. +'level'+ cannot be
4341 defaulted if the first +'command'+ argument starts with a digit or +#+.
4343 For example, suppose that procedure 'a' was invoked
4344 from top-level, and that it called 'b', and that 'b' called 'c'.
4345 Suppose that 'c' invokes the `uplevel` command. If +'level'+
4346 is +1+ or +#2+ or omitted, then the command will be executed
4347 in the variable context of 'b'. If +'level'+ is +2+ or +#1+
4348 then the command will be executed in the variable context of 'a'.
4350 If +'level'+ is '3' or +#0+ then the command will be executed
4351 at top-level (only global variables will be visible).
4352 The `uplevel` command causes the invoking procedure to disappear
4353 from the procedure calling stack while the command is being executed.
4354 In the above example, suppose 'c' invokes the command
4356 uplevel 1 {set x 43; d}
4358 where 'd' is another Tcl procedure. The `set` command will
4359 modify the variable 'x' in 'b's context, and 'd' will execute
4360 at level 3, as if called from 'b'. If it in turn executes
4365 then the `set` command will modify the same variable 'x' in 'b's
4366 context: the procedure 'c' does not appear to be on the call stack
4367 when 'd' is executing. The command `info level` may
4368 be used to obtain the level of the current procedure.
4370 `uplevel` makes it possible to implement new control
4371 constructs as Tcl procedures (for example, `uplevel` could
4372 be used to implement the `while` construct as a Tcl procedure).
4376 +*upvar* '?level? otherVar myVar ?otherVar myVar ...?'+
4378 This command arranges for one or more local variables in the current
4379 procedure to refer to variables in an enclosing procedure call or
4380 to global variables.
4382 +'level'+ may have any of the forms permitted for the `uplevel`
4383 command, and may be omitted if the first letter of the first +'otherVar'+
4384 isn't +#+ or a digit (it defaults to '1').
4386 For each +'otherVar'+ argument, `upvar` makes the variable
4387 by that name in the procedure frame given by +'level'+ (or at
4388 global level, if +'level'+ is +#0+) accessible
4389 in the current procedure by the name given in the corresponding
4392 The variable named by +'otherVar'+ need not exist at the time of the
4393 call; it will be created the first time +'myVar'+ is referenced, just like
4394 an ordinary variable.
4396 `upvar` may only be invoked from within procedures.
4398 `upvar` returns an empty string.
4400 The `upvar` command simplifies the implementation of call-by-name
4401 procedure calling and also makes it easier to build new control constructs
4403 For example, consider the following procedure:
4410 'add2' is invoked with an argument giving the name of a variable,
4411 and it adds two to the value of that variable.
4412 Although 'add2' could have been implemented using `uplevel`
4413 instead of `upvar`, `upvar` makes it simpler for 'add2'
4414 to access the variable in the caller's procedure frame.
4418 +*while* 'test body'+
4420 The +'while'+ command evaluates +'test'+ as an expression
4421 (in the same way that `expr` evaluates its argument).
4422 The value of the expression must be numeric; if it is non-zero
4423 then +'body'+ is executed by passing it to the Tcl interpreter.
4425 Once +'body'+ has been executed then +'test'+ is evaluated
4426 again, and the process repeats until eventually +'test'+
4427 evaluates to a zero numeric value. `continue`
4428 commands may be executed inside +'body'+ to terminate the current
4429 iteration of the loop, and `break`
4430 commands may be executed inside +'body'+ to cause immediate
4431 termination of the `while` command.
4433 The `while` command always returns an empty string.
4438 The following extensions may or may not be available depending upon
4439 what options were selected when Jim Tcl was built.
4442 posix: os.fork, os.wait, os.gethostname, os.getids, os.uptime
4443 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4445 Invokes 'fork(2)' and returns the result.
4447 +*os.wait -nohang* 'pid'+::
4448 Invokes waitpid(2), with WNOHANG if +-nohang+ is specified.
4449 Returns a list of 3 elements.
4451 {0 none 0} if -nohang is specified, and the process is still alive.
4453 {-1 error <error-description>} if the process does not exist or has already been waited for.
4455 {<pid> exit <exit-status>} if the process exited normally.
4457 {<pid> signal <signal-number>} if the process terminated on a signal.
4459 {<pid> other 0} otherwise (core dump, stopped, continued, etc.)
4461 +*os.gethostname*+::
4462 Invokes 'gethostname(3)' and returns the result.
4465 Returns the various user/group ids for the current process.
4468 uid 1000 euid 1000 gid 100 egid 100
4471 Returns the number of seconds since system boot. See description of 'uptime' in 'sysinfo(2)'.
4473 ANSI I/O (aio) and EVENTLOOP API
4474 --------------------------------
4475 Jim provides an alternative object-based API for I/O.
4477 See `open` and `socket` for commands which return an I/O handle.
4481 +$handle *accept* ?addrvar?+::
4482 Server socket only: Accept a connection and return stream.
4483 If +'addrvar'+ is specified, the address of the connected client is stored
4484 in the named variable in the form 'addr:port'. See `socket` for details.
4486 +$handle *buffering none|line|full*+::
4487 Sets the buffering mode of the stream.
4489 +$handle *close* ?r(ead)|w(rite)?+::
4491 The two-argument form is a "half-close" on a socket. See the +shutdown(2)+ man page.
4493 +$handle *copyto* 'tofd ?size?'+::
4494 Copy bytes to the file descriptor +'tofd'+. If +'size'+ is specified, at most
4495 that many bytes will be copied. Otherwise copying continues until the end
4496 of the input file. Returns the number of bytes actually copied.
4499 Returns 1 if stream is at eof
4501 +$handle *filename*+::
4502 Returns the original filename associated with the handle.
4503 Handles returned by `socket` give the socket type instead of a filename.
4508 +$handle *gets* '?var?'+::
4509 Read one line and return it or store it in the var
4511 +$handle *isatty*+::
4512 Returns 1 if the stream is a tty device.
4514 +$handle *ndelay ?0|1?*+::
4515 Set O_NDELAY (if arg). Returns current/new setting.
4516 Note that in general ANSI I/O interacts badly with non-blocking I/O.
4519 +$handle *puts ?-nonewline?* 'str'+::
4520 Write the string, with newline unless -nonewline
4522 +$handle *read ?-nonewline?* '?len?'+::
4523 Read and return bytes from the stream. To eof if no len.
4525 +$handle *recvfrom* 'maxlen ?addrvar?'+::
4526 Receives a message from the handle via recvfrom(2) and returns it.
4527 At most +'maxlen'+ bytes are read.
4528 If +'addrvar'+ is specified, the sending address of the message is stored in
4529 the named variable in the form 'addr:port'. See `socket` for details.
4531 +$handle *seek* 'offset' *?start|current|end?*+::
4532 Seeks in the stream (default 'current')
4534 +$handle *sendto* 'str ?addr:?port'+::
4535 Sends the string, +'str'+, to the given address via the socket using sendto(2).
4536 This is intended for udp/dgram sockets and may give an error or behave in unintended
4537 ways for other handle types.
4538 Returns the number of bytes written.
4541 Flush the stream, then fsync(2) to commit any changes to storage.
4542 Only available on platforms that support fsync(2).
4545 Returns the current seek position
4547 +$handle *ssl* *?-server cert priv?*+::
4548 Initiates a SSL/TLS session and returns a new stream
4550 +$handle *verify*+::
4551 Verifies the certificate of a SSL/TLS stream peer
4553 +*load_ssl_certs* 'dir'+::
4554 Loads SSL/TLS CA certificates for use during verification
4558 +*fconfigure* 'handle' *?-blocking 0|1? ?-buffering noneline|full? ?-translation* 'mode'?+::
4559 For compatibility with Tcl, a limited form of the `fconfigure`
4560 command is supported.
4561 * `fconfigure ... -blocking` maps to `aio ndelay`
4562 * `fconfigure ... -buffering` maps to `aio buffering`
4563 * `fconfigure ... -translation` is accepted but ignored
4566 eventloop: after, vwait, update
4567 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4569 The following commands allow a script to be invoked when the given condition occurs.
4570 If no script is given, returns the current script. If the given script is the empty, the
4573 +$handle *readable* '?readable-script?'+::
4574 Sets or returns the script for when the socket is readable.
4576 +$handle *writable* '?writable-script?'+::
4577 Sets or returns the script for when the socket is writable.
4579 +$handle *onexception* '?exception-script?'+::
4580 Sets or returns the script for when oob data received.
4582 For compatibility with 'Tcl', these may be prefixed with `fileevent`. e.g.
4585 +fileevent $handle *readable* '\...'+
4587 Time-based execution is also available via the eventloop API.
4590 Sleeps for the given number of milliseconds. No events are
4591 processed during this time.
4593 +*after* 'ms'|*idle* 'script ?script \...?'+::
4594 The scripts are concatenated and executed after the given
4595 number of milliseconds have elapsed. If 'idle' is specified,
4596 the script will run the next time the event loop is processed
4597 with `vwait` or `update`. The script is only run once and
4598 then removed. Returns an event id.
4600 +*after cancel* 'id|command'+::
4601 Cancels an `after` event with the given event id or matching
4602 command (script). Returns the number of milliseconds
4603 remaining until the event would have fired. Returns the
4604 empty string if no matching event is found.
4606 +*after info* '?id?'+::
4607 If +'id'+ is not given, returns a list of current `after`
4608 events. If +'id'+ is given, returns a list containing the
4609 associated script and either 'timer' or 'idle' to indicated
4610 the type of the event. An error occurs if +'id'+ does not
4613 +*vwait* 'variable'+::
4614 A call to `vwait` is enters the eventloop. `vwait` processes
4615 events until the named (global) variable changes or all
4616 event handlers are removed. The variable need not exist
4617 beforehand. If there are no event handlers defined, `vwait`
4618 returns immediately.
4620 +*update ?idletasks?*+::
4621 A call to `update` enters the eventloop to process expired events, but
4622 no new events. If 'idletasks' is specified, only expired time events are handled,
4624 Returns once handlers have been run for all expired events.
4626 Scripts are executed at the global scope. If an error occurs during a handler script,
4627 an attempt is made to call (the user-defined command) `bgerror` with the details of the error.
4628 If the `bgerror` command does not exist, the error message details are printed to stderr instead.
4630 If a file event handler script generates an error, the handler is automatically removed
4631 to prevent infinite errors. (A time event handler is always removed after execution).
4634 Called when an event handler script generates an error. Note that the normal command resolution
4635 rules are used for bgerror. First the name is resolved in the current namespace, then in the
4640 Various socket types may be created.
4642 +*socket unix* 'path'+::
4643 A unix domain socket client.
4645 +*socket unix.server* 'path'+::
4646 A unix domain socket server.
4648 +*socket ?-ipv6? stream* 'addr:port'+::
4649 A TCP socket client. (See the forms for +'addr'+ below)
4651 +*socket ?-ipv6? stream.server* '?addr:?port'+::
4652 A TCP socket server (+'addr'+ defaults to +0.0.0.0+ for IPv4 or +[::]+ for IPv6).
4654 +*socket ?-ipv6? dgram* ?'addr:port'?+::
4655 A UDP socket client. If the address is not specified,
4656 the client socket will be unbound and 'sendto' must be used
4657 to indicated the destination.
4659 +*socket ?-ipv6? dgram.server* 'addr:port'+::
4660 A UDP socket server.
4663 A pipe. Note that unlike all other socket types, this command returns
4664 a list of two channels: {read write}
4667 A socketpair (see socketpair(2)). Like `socket pipe`, this command returns
4668 a list of two channels: {s1 s2}. These channels are both readable and writable.
4670 This command creates a socket connected (client) or bound (server) to the given
4673 The returned value is channel and may generally be used with the various file I/O
4674 commands (gets, puts, read, etc.), either as object-based syntax or Tcl-compatible syntax.
4676 set f [socket stream www.google.com:80]
4678 $f puts -nonewline "GET / HTTP/1.0\r\n\r\n"
4683 Server sockets, however support only 'accept', which is most useful in conjunction with
4686 set f [socket stream.server 80]
4688 set client [$f accept]
4691 $client puts -nonewline "HTTP/1.1 404 Not found\r\n"
4696 The address, +'addr'+, can be given in one of the following forms:
4698 1. For IPv4 socket types, an IPv4 address such as 192.168.1.1
4699 2. For IPv6 socket types, an IPv6 address such as [fe80::1234] or [::]
4702 Note that on many systems, listening on an IPv6 address such as [::] will
4703 also accept requests via IPv4.
4705 Where a hostname is specified, the +'first'+ returned address is used
4706 which matches the socket type is used.
4708 The special type 'pipe' isn't really a socket.
4710 lassign [socket pipe] r w
4712 # Must close $w after exec
4720 +*syslog* '?options? ?priority? message'+
4722 This command sends message to system syslog facility with given
4723 priority. Valid priorities are:
4725 emerg, alert, crit, err, error, warning, notice, info, debug
4727 If a message is specified, but no priority is specified, then a
4728 priority of info is used.
4730 By default, facility user is used and the value of global tcl variable
4731 argv0 is used as ident string. However, any of the following options
4732 may be specified before priority to control these parameters:
4734 +*-facility* 'value'+::
4735 Use specified facility instead of user. The following
4736 values for facility are recognized:
4738 authpriv, cron, daemon, kernel, lpr, mail, news, syslog, user,
4741 +*-ident* 'string'+::
4742 Use given string instead of argv0 variable for ident string.
4744 +*-options* 'integer'+::
4745 Set syslog options such as +LOG_CONS+, +LOG_NDELAY+. You should
4746 use numeric values of those from your system syslog.h file,
4747 because I haven't got time to implement yet another hash
4752 The optional 'pack' extension provides commands to encode and decode binary strings.
4754 +*pack* 'varName value' *-intle|-intbe|-floatle|-floatbe|-str* 'bitwidth ?bitoffset?'+::
4755 Packs the binary representation of +'value'+ into the variable
4756 +'varName'+. The value is packed according to the given type
4757 (integer/floating point/string, big-endian/little-endian), width and bit offset.
4758 The variable is created if necessary (like `append`).
4759 The variable is expanded if necessary.
4761 +*unpack* 'binvalue' *-intbe|-intle|-uintbe|-uintle|-floatbe|-floatle|-str* 'bitpos bitwidth'+::
4762 Unpacks bits from +'binvalue'+ at bit position +'bitpos'+ and with +'bitwidth'+.
4763 Interprets the value according to the type (integer/floating point/string, big-endian/little-endian
4764 and signed/unsigned) and returns it. For integer types, +'bitwidth'+
4765 may be up to the size of a Jim Tcl integer (typically 64 bits). For floating point types,
4766 +'bitwidth'+ may be 32 bits (for single precision numbers) or 64 bits (for double precision).
4767 For the string type, both the width and the offset must be on a byte boundary (multiple of 8). Attempting to
4768 access outside the length of the value will return 0 for integer types, 0.0 for floating point types
4769 or the empty string for the string type.
4773 The optional 'zlib' extension provides a is a Tcl-compatible subset of the `zlib` command.
4775 +*crc32* 'data' '?startValue?'+::
4776 Returns the CRC32 checksum of a buffer. Optionally, an initial value may be specified; this is most useful
4777 for calculating the checksum of chunked data read from a stream (for instance, a pipe).
4779 +*deflate* 'string' '?level?'+::
4780 Compresses a buffer and outputs a raw, Deflate-compressed stream. Optionally, a compression level (1-9) may
4781 be specified to choose the desired speed vs. compression rate ratio.
4783 +*inflate* 'data' '?bufferSize?'+::
4784 Decompresses a raw, Deflate-compressed stream. When the uncompressed data size is known and specified, memory
4785 allocation is more efficient. Otherwise, decomperssion is chunked and therefore slower.
4787 +*gzip* 'string' '?-level level?'+::
4788 Compresses a buffer and adds a gzip header.
4790 +*gunzip* 'data' '?-buffersize size?'+::
4791 Decompresses a gzip-compressed buffer. Decompression is chunked, with a default, small buffer size of 64K
4792 which guarantees lower memory footprint at the cost of speed. It is recommended to use a bigger size, on
4793 systems without a severe memory constraint.
4797 The optional, pure-Tcl 'binary' extension provides the Tcl-compatible `binary scan` and `binary format`
4798 commands based on the low-level `pack` and `unpack` commands.
4800 See the Tcl documentation at: http://www.tcl.tk/man/tcl8.5/TclCmd/binary.htm
4802 Note that 'binary format' with f/r/R specifiers (single-precision float) uses the value of Infinity
4803 in case of overflow.
4807 The optional, pure-Tcl 'oo' extension provides object-oriented (OO) support for Jim Tcl.
4809 See the online documentation (http://jim.tcl.tk/index.html/doc/www/www/documentation/oo/) for more details.
4811 +*class* 'classname ?baseclasses? classvars'+::
4812 Create a new class, +'classname'+, with the given dictionary
4813 (+'classvars'+) as class variables. These are the initial variables
4814 which all newly created objects of this class are initialised with.
4815 If a list of baseclasses is given, methods and instance variables
4818 +*super* 'method ?args \...?'+::
4819 From within a method, invokes the given method on the base class.
4820 Note that this will only call the last baseclass given.
4824 The optional, pure-Tcl 'tree' extension implements an OO, general purpose tree structure
4825 similar to that provided by tcllib ::struct::tree (http://core.tcl.tk/tcllib/doc/trunk/embedded/www/tcllib/files/modules/struct/struct_tree.html)
4827 A tree is a collection of nodes, where each node (except the root node) has a single parent
4828 and zero or more child nodes (ordered), as well as zero or more attribute/value pairs.
4831 Creates and returns a new tree object with a single node named "root".
4832 All operations on the tree are invoked through this object.
4835 Destroy the tree and all it's nodes. (Note that the tree will also
4836 be automatically garbage collected once it goes out of scope).
4838 +$tree *set* 'nodename key value'+::
4839 Set the value for the given attribute key.
4841 +$tree *lappend* 'nodename key value \...'+::
4842 Append to the (list) value(s) for the given attribute key, or set if not yet set.
4844 +$tree *keyexists* 'nodename key'+::
4845 Returns 1 if the given attribute key exists.
4847 +$tree *get* 'nodename key'+::
4848 Returns the value associated with the given attribute key.
4850 +$tree *getall* 'nodename'+::
4851 Returns the entire attribute dictionary associated with the given key.
4853 +$tree *depth* 'nodename'+::
4854 Returns the depth of the given node. The depth of "root" is 0.
4856 +$tree *parent* 'nodename'+::
4857 Returns the node name of the parent node, or "" for the root node.
4859 +$tree *numchildren* 'nodename'+::
4860 Returns the number of child nodes.
4862 +$tree *children* 'nodename'+::
4863 Returns a list of the child nodes.
4865 +$tree *next* 'nodename'+::
4866 Returns the next sibling node, or "" if none.
4868 +$tree *insert* 'nodename ?index?'+::
4869 Add a new child node to the given node. The index is a list index
4870 such as +3+ or +end-2+. The default index is +end+.
4871 Returns the name of the newly added node.
4873 +$tree *walk* 'nodename' *dfs|bfs* {'actionvar nodevar'} 'script'+::
4874 Walks the tree starting from the given node, either breadth first (+bfs+)
4875 depth first (+dfs+).
4876 The value +"enter"+ or +"exit"+ is stored in variable +'actionvar'+.
4877 The name of each node is stored in +'nodevar'+.
4878 The script is evaluated twice for each node, on entry and exit.
4881 Dumps the tree contents to stdout
4885 The optional tclprefix extension provides the Tcl8.6-compatible 'tcl::prefix' command
4886 (http://www.tcl.tk/man/tcl8.6/TclCmd/prefix.htm) for matching strings against a table
4887 of possible values (typically commands or options).
4889 +*tcl::prefix all* 'table string'+::
4890 Returns a list of all elements in +'table'+ that begin with the prefix +'string'+.
4892 +*tcl::prefix longest* 'table string'+::
4893 Returns the longest common prefix of all elements in +'table'+ that begin with the prefix +'string'+.
4895 +*tcl::prefix match* '?options? table string'+::
4896 If +'string'+ equals one element in +'table'+ or is a prefix to
4897 exactly one element, the matched element is returned. If not, the
4898 result depends on the +-error+ option.
4900 * +*-exact*+ Accept only exact matches.
4901 * +*-message* 'string'+ Use +'string'+ in the error message at a mismatch. Default is "option".
4902 * +*-error* 'options'+ The options are used when no match is found. If +'options'+ is
4903 empty, no error is generated and an empty string is returned.
4904 Otherwise the options are used as return options when
4905 generating the error message. The default corresponds to
4910 The optional history extension provides script access to the command line editing
4911 and history support available in 'jimsh'. See 'examples/jtclsh.tcl' for an example.
4912 Note: if line editing support is not available, `history getline` acts like `gets` and
4913 the remaining subcommands do nothing.
4915 +*history load* 'filename'+::
4916 Load history from a (text) file. If the file does not exist or is not readable,
4919 +*history getline* 'prompt ?varname?'+::
4920 Displays the given prompt and allows a line to be entered. Similarly to `gets`,
4921 if +'varname'+ is given, it receives the line and the length of the line is returned,
4922 or -1 on EOF. If +'varname'+ is not given, the line is returned directly.
4924 +*history add* 'line'+::
4925 Adds the given line to the history buffer.
4927 +*history save* 'filename'+::
4928 Saves the current history buffer to the given file.
4931 Displays the current history buffer to standard output.
4935 Provides namespace-related functions. See also: http://www.tcl.tk/man/tcl8.6/TclCmd/namespace.htm
4937 +*namespace code* 'script'+::
4938 Captures the current namespace context for later execution of
4939 the script +'script'+. It returns a new script in which script has
4940 been wrapped in a +*namespace inscope*+ command.
4942 +*namespace current*+::
4943 Returns the fully-qualified name for the current namespace.
4945 +*namespace delete* '?namespace ...?'+::
4946 Deletes all commands and variables with the given namespace prefixes.
4948 +*namespace eval* 'namespace arg ?arg...?'+::
4949 Activates a namespace called +'namespace'+ and evaluates some code in that context.
4951 +*namespace origin* 'command'+::
4952 Returns the fully-qualified name of the original command to which the imported command +'command'+ refers.
4954 +*namespace parent* ?namespace?+::
4955 Returns the fully-qualified name of the parent namespace for namespace +'namespace'+, if given, otherwise
4956 for the current namespace.
4958 +*namespace qualifiers* 'string'+::
4959 Returns any leading namespace qualifiers for +'string'+
4961 +*namespace tail* 'string'+::
4962 Returns the simple name at the end of a qualified string.
4964 +*namespace upvar* 'namespace ?arg...?'+::
4965 This command arranges for zero or more local variables in the current procedure to refer to variables in +'namespace'+
4967 +*namespace which* '?-command|-variable? name'+::
4968 Looks up +'name'+ as either a command (the default) or variable and returns its fully-qualified name.
4970 [[BuiltinVariables]]
4974 The following global variables are created automatically
4978 This variable is set by Jim as an array
4979 whose elements are the environment variables for the process.
4980 Reading an element will return the value of the corresponding
4981 environment variable.
4982 This array is initialised at startup from the `env` command.
4983 It may be modified and will affect the environment passed to
4984 commands invoked with `exec`.
4987 This variable is set by Jim as an array containing information
4988 about the platform on which Jim was built. Currently this includes
4989 'os' and 'platform'.
4992 This variable contains a list of paths to search for packages.
4993 It defaults to a location based on where jim is installed
4994 (e.g. +/usr/local/lib/jim+), but may be changed by +jimsh+
4995 or the embedding application. Note that +jimsh+ will consider
4996 the environment variable +$JIMLIB+ to be a list of colon-separated
4997 list of paths to add to +*auto_path*+.
5000 This variable holds the value of the -errorcode return
5001 option set by the most recent error that occurred in this
5002 interpreter. This list value represents additional information
5003 about the error in a form that is easy to process with
5004 programs. The first element of the list identifies a general
5005 class of errors, and determines the format of the rest of
5006 the list. The following formats for -errorcode return options
5007 are used by the Tcl core; individual applications may define
5008 additional formats. Currently only `exec` sets this variable.
5009 Otherwise it will be +NONE+.
5011 The following global variables are set by jimsh.
5013 +*tcl_interactive*+::
5014 This variable is set to 1 if jimsh is started in interactive mode
5018 This variable is set by Jim as an array containing information
5019 about the platform upon which Jim was built. The following is an
5020 example of the contents of this array.
5022 tcl_platform(byteOrder) = littleEndian
5023 tcl_platform(engine) = Jim
5024 tcl_platform(os) = Darwin
5025 tcl_platform(platform) = unix
5026 tcl_platform(pointerSize) = 8
5027 tcl_platform(threaded) = 0
5028 tcl_platform(wordSize) = 8
5029 tcl_platform(pathSeparator) = :
5032 If jimsh is invoked to run a script, this variable contains the name
5036 If jimsh is invoked to run a script, this variable contains a list
5037 of any arguments supplied to the script.
5040 If jimsh is invoked to run a script, this variable contains the number
5041 of arguments supplied to the script.
5044 The value of argv[0] when jimsh was invoked.
5046 CHANGES IN PREVIOUS RELEASES
5047 ----------------------------
5051 1. +platform_tcl()+ settings are now automatically determined
5052 2. Add aio `$handle filename`
5053 3. Add `info channels`
5054 4. The 'bio' extension is gone. Now `aio` supports 'copyto'.
5055 5. Add `exists` command
5056 6. Add the pure-Tcl 'oo' extension
5057 7. The `exec` command now only uses vfork(), not fork()
5058 8. Unit test framework is less verbose and more Tcl-compatible
5059 9. Optional UTF-8 support
5060 10. Optional built-in regexp engine for better Tcl compatibility and UTF-8 support
5061 11. Command line editing in interactive mode, e.g. 'jimsh'
5065 1. `source` now checks that a script is complete (.i.e. not missing a brace)
5066 2. 'info complete' now uses the real parser and so is 100% accurate
5067 3. Better access to live stack frames with 'info frame', `stacktrace` and `stackdump`
5068 4. `tailcall` no longer loses stack trace information
5069 5. Add `alias` and `curry`
5070 6. `lambda`, `alias` and `curry` are implemented via `tailcall` for efficiency
5071 7. `local` allows procedures to be deleted automatically at the end of the current procedure
5072 8. udp sockets are now supported for both clients and servers.
5073 9. vfork-based exec is now working correctly
5074 10. Add 'file tempfile'
5075 11. Add 'socket pipe'
5076 12. Enhance 'try ... on ... finally' to be more Tcl 8.6 compatible
5077 13. It is now possible to `return` from within `try`
5078 14. IPv6 support is now included
5080 16. Event handlers works better if an error occurs. eof handler has been removed.
5081 17. `exec` now sets $::errorCode, and catch sets opts(-errorcode) for exit status
5082 18. Command pipelines via open "|..." are now supported
5083 19. `pid` can now return pids of a command pipeline
5084 20. Add 'info references'
5085 21. Add support for 'after +'ms'+', 'after idle', 'after info', `update`
5086 22. `exec` now sets environment based on $::env
5088 24. Add support for 'lsort -index'
5092 1. Add support to `exec` for '>&', '>>&', '|&', '2>@1'
5093 2. Fix `exec` error messages when special token (e.g. '>') is the last token
5094 3. Fix `subst` handling of backslash escapes.
5095 4. Allow abbreviated options for `subst`
5096 5. Add support for `return`, `break`, `continue` in subst
5097 6. Many `expr` bug fixes
5098 7. Add support for functions in `expr` (e.g. int(), abs()), and also 'in', 'ni' list operations
5099 8. The variable name argument to `regsub` is now optional
5100 9. Add support for 'unset -nocomplain'
5101 10. Add support for list commands: `lassign`, `lrepeat`
5102 11. Fully-functional `lsearch` is now implemented
5103 12. Add 'info nameofexecutable' and 'info returncodes'
5104 13. Allow `catch` to determine what return codes are caught
5105 14. Allow `incr` to increment an unset variable by first setting to 0
5106 15. Allow 'args' and optional arguments to the left or required arguments in `proc`
5108 17. Add 'try ... finally' command
5114 Copyright 2005 Salvatore Sanfilippo <antirez@invece.org>
5115 Copyright 2005 Clemens Hintze <c.hintze@gmx.net>
5116 Copyright 2005 patthoyts - Pat Thoyts <patthoyts@users.sf.net>
5117 Copyright 2008 oharboe - Oyvind Harboe - oyvind.harboe@zylin.com
5118 Copyright 2008 Andrew Lunn <andrew@lunn.ch>
5119 Copyright 2008 Duane Ellis <openocd@duaneellis.com>
5120 Copyright 2008 Uwe Klein <uklein@klein-messgeraete.de>
5121 Copyright 2009 Steve Bennett <steveb@workware.net.au>
5124 Redistribution and use in source and binary forms, with or without
5125 modification, are permitted provided that the following conditions
5127 1. Redistributions of source code must retain the above copyright
5128 notice, this list of conditions and the following disclaimer.
5129 2. Redistributions in binary form must reproduce the above
5130 copyright notice, this list of conditions and the following
5131 disclaimer in the documentation and/or other materials
5132 provided with the distribution.
5134 THIS SOFTWARE IS PROVIDED BY THE JIM TCL PROJECT ``AS IS'' AND ANY
5135 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
5136 THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
5137 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
5138 JIM TCL PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
5139 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
5140 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
5141 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
5142 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
5143 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
5144 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
5145 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
5147 The views and conclusions contained in the software and documentation
5148 are those of the authors and should not be interpreted as representing
5149 official policies, either expressed or implied, of the Jim Tcl Project.