1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities.
9 * ar: (binutils)ar. Create, modify, and extract from archives
10 * nm: (binutils)nm. List symbols from object files
11 * objcopy: (binutils)objcopy. Copy and translate object files
12 * objdump: (binutils)objdump. Display information from object files
13 * ranlib: (binutils)ranlib. Generate index to archive contents
14 * readelf: (binutils)readelf. Display the contents of ELF format files.
15 * size: (binutils)size. List section sizes and total size
16 * strings: (binutils)strings. List printable strings from files
17 * strip: (binutils)strip. Discard symbols
18 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
19 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
20 * addr2line: (binutils)addr2line. Convert addresses to file and line
21 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
22 * windres: (binutils)windres. Manipulate Windows resources
23 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
29 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
31 Permission is granted to make and distribute verbatim copies of
32 this manual provided the copyright notice and this permission notice
33 are preserved on all copies.
36 Permission is granted to process this file through TeX and print the
37 results, provided the printed document carries a copying permission
38 notice identical to this one except for the removal of this paragraph
39 (this paragraph not being relevant to the printed manual).
43 Permission is granted to copy and distribute modified versions of this
44 manual under the conditions for verbatim copying, provided also that
45 the entire resulting derived work is distributed under the terms of a
46 permission notice identical to this one.
48 Permission is granted to copy and distribute translations of this manual
49 into another language, under the above conditions for modified versions.
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
57 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
59 @c This text may be freely distributed under the terms of the GNU
60 @c General Public License.
63 @setchapternewpage odd
64 @settitle @sc{gnu} Binary Utilities
67 @title The @sc{gnu} Binary Utilities
68 @subtitle Version @value{VERSION}
71 @author Roland H. Pesch
72 @author Jeffrey M. Osier
73 @author Cygnus Support
77 {\parskip=0pt \hfill Cygnus Support\par \hfill
78 \TeX{}info \texinfoversion\par }
81 @vskip 0pt plus 1filll
82 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
84 Permission is granted to make and distribute verbatim copies of
85 this manual provided the copyright notice and this permission notice
86 are preserved on all copies.
88 Permission is granted to copy and distribute modified versions of this
89 manual under the conditions for verbatim copying, provided also that
90 the entire resulting derived work is distributed under the terms of a
91 permission notice identical to this one.
93 Permission is granted to copy and distribute translations of this manual
94 into another language, under the above conditions for modified versions.
101 This brief manual contains preliminary documentation for the @sc{gnu} binary
102 utilities (collectively version @value{VERSION}):
107 Create, modify, and extract from archives
110 List symbols from object files
113 Copy and translate object files
116 Display information from object files
119 Generate index to archive contents
122 Display the contents of ELF format files.
125 List file section sizes and total size
128 List printable strings from files
134 Demangle encoded C++ symbols (on MS-DOS, this program is named
138 Convert addresses into file names and line numbers
141 Convert object code into a Netware Loadable Module
144 Manipulate Windows resources
147 Create the files needed to build and use Dynamic Link Libraries
152 * ar:: Create, modify, and extract from archives
153 * nm:: List symbols from object files
154 * objcopy:: Copy and translate object files
155 * objdump:: Display information from object files
156 * ranlib:: Generate index to archive contents
157 * readelf:: Display the contents of ELF format files.
158 * size:: List section sizes and total size
159 * strings:: List printable strings from files
160 * strip:: Discard symbols
161 * c++filt:: Filter to demangle encoded C++ symbols
162 * cxxfilt: c++filt. MS-DOS name for c++filt
163 * addr2line:: Convert addresses to file and line
164 * nlmconv:: Converts object code into an NLM
165 * windres:: Manipulate Windows resources
166 * dlltool:: Create files needed to build and use DLLs
167 * Selecting The Target System:: How these utilities determine the target.
168 * Reporting Bugs:: Reporting Bugs
177 @cindex collections of files
179 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
180 ar -M [ <mri-script ]
183 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
193 @sc{gnu} @code{ar} can maintain archives whose members have names of any
194 length; however, depending on how @code{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
201 @code{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @code{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @code{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @code{ar} called
216 @code{ranlib} can be used to add just the table.
218 @cindex compatibility, @code{ar}
219 @cindex @code{ar} compatibility
220 @sc{gnu} @code{ar} is designed to be compatible with two different
221 facilities. You can control its activity using command-line options,
222 like the different varieties of @code{ar} on Unix systems; or, if you
223 specify the single command-line option @samp{-M}, you can control it
224 with a script supplied via standard input, like the MRI ``librarian''
228 * ar cmdline:: Controlling @code{ar} on the command line
229 * ar scripts:: Controlling @code{ar} with a script
234 @section Controlling @code{ar} on the command line
237 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
240 @cindex Unix compatibility, @code{ar}
241 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
242 arguments to execute: one keyletter specifying the @emph{operation}
243 (optionally accompanied by other keyletters specifying
244 @emph{modifiers}), and the archive name to act on.
246 Most operations can also accept further @var{member} arguments,
247 specifying particular files to operate on.
249 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
250 flags @var{mod} in any order, within the first command-line argument.
252 If you wish, you may begin the first command-line argument with a
255 @cindex operations on archive
256 The @var{p} keyletter specifies what operation to execute; it may be
257 any of the following, but you must specify only one of them:
261 @cindex deleting from archive
262 @emph{Delete} modules from the archive. Specify the names of modules to
263 be deleted as @var{member}@dots{}; the archive is untouched if you
264 specify no files to delete.
266 If you specify the @samp{v} modifier, @code{ar} lists each module
270 @cindex moving in archive
271 Use this operation to @emph{move} members in an archive.
273 The ordering of members in an archive can make a difference in how
274 programs are linked using the library, if a symbol is defined in more
277 If no modifiers are used with @code{m}, any members you name in the
278 @var{member} arguments are moved to the @emph{end} of the archive;
279 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
280 specified place instead.
283 @cindex printing from archive
284 @emph{Print} the specified members of the archive, to the standard
285 output file. If the @samp{v} modifier is specified, show the member
286 name before copying its contents to standard output.
288 If you specify no @var{member} arguments, all the files in the archive are
292 @cindex quick append to archive
293 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
294 @var{archive}, without checking for replacement.
296 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
297 operation; new members are always placed at the end of the archive.
299 The modifier @samp{v} makes @code{ar} list each file as it is appended.
301 Since the point of this operation is speed, the archive's symbol table
302 index is not updated, even if it already existed; you can use @samp{ar s} or
303 @code{ranlib} explicitly to update the symbol table index.
305 However, too many different systems assume quick append rebuilds the
306 index, so GNU ar implements @code{q} as a synonym for @code{r}.
309 @cindex replacement in archive
310 Insert the files @var{member}@dots{} into @var{archive} (with
311 @emph{replacement}). This operation differs from @samp{q} in that any
312 previously existing members are deleted if their names match those being
315 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
316 displays an error message, and leaves undisturbed any existing members
317 of the archive matching that name.
319 By default, new members are added at the end of the file; but you may
320 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
321 placement relative to some existing member.
323 The modifier @samp{v} used with this operation elicits a line of
324 output for each file inserted, along with one of the letters @samp{a} or
325 @samp{r} to indicate whether the file was appended (no old member
326 deleted) or replaced.
329 @cindex contents of archive
330 Display a @emph{table} listing the contents of @var{archive}, or those
331 of the files listed in @var{member}@dots{} that are present in the
332 archive. Normally only the member name is shown; if you also want to
333 see the modes (permissions), timestamp, owner, group, and size, you can
334 request that by also specifying the @samp{v} modifier.
336 If you do not specify a @var{member}, all files in the archive
339 @cindex repeated names in archive
340 @cindex name duplication in archive
341 If there is more than one file with the same name (say, @samp{fie}) in
342 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
343 first instance; to see them all, you must ask for a complete
344 listing---in our example, @samp{ar t b.a}.
345 @c WRS only; per Gumby, this is implementation-dependent, and in a more
346 @c recent case in fact works the other way.
349 @cindex extract from archive
350 @emph{Extract} members (named @var{member}) from the archive. You can
351 use the @samp{v} modifier with this operation, to request that
352 @code{ar} list each name as it extracts it.
354 If you do not specify a @var{member}, all files in the archive
359 A number of modifiers (@var{mod}) may immediately follow the @var{p}
360 keyletter, to specify variations on an operation's behavior:
364 @cindex relative placement in archive
365 Add new files @emph{after} an existing member of the
366 archive. If you use the modifier @samp{a}, the name of an existing archive
367 member must be present as the @var{relpos} argument, before the
368 @var{archive} specification.
371 Add new files @emph{before} an existing member of the
372 archive. If you use the modifier @samp{b}, the name of an existing archive
373 member must be present as the @var{relpos} argument, before the
374 @var{archive} specification. (same as @samp{i}).
377 @cindex creating archives
378 @emph{Create} the archive. The specified @var{archive} is always
379 created if it did not exist, when you request an update. But a warning is
380 issued unless you specify in advance that you expect to create it, by
384 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
385 names of any length. This will cause it to create archives which are
386 not compatible with the native @code{ar} program on some systems. If
387 this is a concern, the @samp{f} modifier may be used to truncate file
388 names when putting them in the archive.
391 Insert new files @emph{before} an existing member of the
392 archive. If you use the modifier @samp{i}, the name of an existing archive
393 member must be present as the @var{relpos} argument, before the
394 @var{archive} specification. (same as @samp{b}).
397 This modifier is accepted but not used.
398 @c whaffor ar l modifier??? presumably compat; with
399 @c what???---doc@@cygnus.com, 25jan91
402 Uses the @var{count} parameter. This is used if there are multiple
403 entries in the archive with the same name. Extract or delete instance
404 @var{count} of the given name from the archive.
407 @cindex dates in archive
408 Preserve the @emph{original} dates of members when extracting them. If
409 you do not specify this modifier, files extracted from the archive
410 are stamped with the time of extraction.
413 Use the full path name when matching names in the archive. @sc{gnu}
414 @code{ar} can not create an archive with a full path name (such archives
415 are not POSIX complaint), but other archive creators can. This option
416 will cause @sc{gnu} @code{ar} to match file names using a complete path
417 name, which can be convenient when extracting a single file from an
418 archive created by another tool.
421 @cindex writing archive index
422 Write an object-file index into the archive, or update an existing one,
423 even if no other change is made to the archive. You may use this modifier
424 flag either with any operation, or alone. Running @samp{ar s} on an
425 archive is equivalent to running @samp{ranlib} on it.
428 @cindex not writing archive index
429 Do not generate an archive symbol table. This can speed up building a
430 large library in several steps. The resulting archive can not be used
431 with the linker. In order to build a symbol table, you must omit the
432 @samp{S} modifier on the last execution of @samp{ar}, or you must run
433 @samp{ranlib} on the archive.
436 @cindex updating an archive
437 Normally, @samp{ar r}@dots{} inserts all files
438 listed into the archive. If you would like to insert @emph{only} those
439 of the files you list that are newer than existing members of the same
440 names, use this modifier. The @samp{u} modifier is allowed only for the
441 operation @samp{r} (replace). In particular, the combination @samp{qu} is
442 not allowed, since checking the timestamps would lose any speed
443 advantage from the operation @samp{q}.
446 This modifier requests the @emph{verbose} version of an operation. Many
447 operations display additional information, such as filenames processed,
448 when the modifier @samp{v} is appended.
451 This modifier shows the version number of @code{ar}.
455 @section Controlling @code{ar} with a script
458 ar -M [ <@var{script} ]
461 @cindex MRI compatibility, @code{ar}
462 @cindex scripts, @code{ar}
463 If you use the single command-line option @samp{-M} with @code{ar}, you
464 can control its operation with a rudimentary command language. This
465 form of @code{ar} operates interactively if standard input is coming
466 directly from a terminal. During interactive use, @code{ar} prompts for
467 input (the prompt is @samp{AR >}), and continues executing even after
468 errors. If you redirect standard input to a script file, no prompts are
469 issued, and @code{ar} abandons execution (with a nonzero exit code)
472 The @code{ar} command language is @emph{not} designed to be equivalent
473 to the command-line options; in fact, it provides somewhat less control
474 over archives. The only purpose of the command language is to ease the
475 transition to @sc{gnu} @code{ar} for developers who already have scripts
476 written for the MRI ``librarian'' program.
478 The syntax for the @code{ar} command language is straightforward:
481 commands are recognized in upper or lower case; for example, @code{LIST}
482 is the same as @code{list}. In the following descriptions, commands are
483 shown in upper case for clarity.
486 a single command may appear on each line; it is the first word on the
490 empty lines are allowed, and have no effect.
493 comments are allowed; text after either of the characters @samp{*}
494 or @samp{;} is ignored.
497 Whenever you use a list of names as part of the argument to an @code{ar}
498 command, you can separate the individual names with either commas or
499 blanks. Commas are shown in the explanations below, for clarity.
502 @samp{+} is used as a line continuation character; if @samp{+} appears
503 at the end of a line, the text on the following line is considered part
504 of the current command.
507 Here are the commands you can use in @code{ar} scripts, or when using
508 @code{ar} interactively. Three of them have special significance:
510 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
511 a temporary file required for most of the other commands.
513 @code{SAVE} commits the changes so far specified by the script. Prior
514 to @code{SAVE}, commands affect only the temporary copy of the current
518 @item ADDLIB @var{archive}
519 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
520 Add all the contents of @var{archive} (or, if specified, each named
521 @var{module} from @var{archive}) to the current archive.
523 Requires prior use of @code{OPEN} or @code{CREATE}.
525 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
526 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
527 @c else like "ar q..."
528 Add each named @var{member} as a module in the current archive.
530 Requires prior use of @code{OPEN} or @code{CREATE}.
533 Discard the contents of the current archive, canceling the effect of
534 any operations since the last @code{SAVE}. May be executed (with no
535 effect) even if no current archive is specified.
537 @item CREATE @var{archive}
538 Creates an archive, and makes it the current archive (required for many
539 other commands). The new archive is created with a temporary name; it
540 is not actually saved as @var{archive} until you use @code{SAVE}.
541 You can overwrite existing archives; similarly, the contents of any
542 existing file named @var{archive} will not be destroyed until @code{SAVE}.
544 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
545 Delete each listed @var{module} from the current archive; equivalent to
546 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
548 Requires prior use of @code{OPEN} or @code{CREATE}.
550 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
551 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
552 List each named @var{module} present in @var{archive}. The separate
553 command @code{VERBOSE} specifies the form of the output: when verbose
554 output is off, output is like that of @samp{ar -t @var{archive}
555 @var{module}@dots{}}. When verbose output is on, the listing is like
556 @samp{ar -tv @var{archive} @var{module}@dots{}}.
558 Output normally goes to the standard output stream; however, if you
559 specify @var{outputfile} as a final argument, @code{ar} directs the
563 Exit from @code{ar}, with a @code{0} exit code to indicate successful
564 completion. This command does not save the output file; if you have
565 changed the current archive since the last @code{SAVE} command, those
568 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
569 Extract each named @var{module} from the current archive, writing them
570 into the current directory as separate files. Equivalent to @samp{ar -x
571 @var{archive} @var{module}@dots{}}.
573 Requires prior use of @code{OPEN} or @code{CREATE}.
576 @c FIXME Tokens but no commands???
583 Display full contents of the current archive, in ``verbose'' style
584 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
585 tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
586 enhancement, rather than present for MRI compatibility.)
588 Requires prior use of @code{OPEN} or @code{CREATE}.
590 @item OPEN @var{archive}
591 Opens an existing archive for use as the current archive (required for
592 many other commands). Any changes as the result of subsequent commands
593 will not actually affect @var{archive} until you next use @code{SAVE}.
595 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
596 In the current archive, replace each existing @var{module} (named in
597 the @code{REPLACE} arguments) from files in the current working directory.
598 To execute this command without errors, both the file, and the module in
599 the current archive, must exist.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 Toggle an internal flag governing the output from @code{DIRECTORY}.
605 When the flag is on, @code{DIRECTORY} output matches output from
606 @samp{ar -tv }@dots{}.
609 Commit your changes to the current archive, and actually save it as a
610 file with the name specified in the last @code{CREATE} or @code{OPEN}
613 Requires prior use of @code{OPEN} or @code{CREATE}.
622 The @sc{gnu} linker @code{ld} is now described in a separate manual.
623 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
632 nm [ -a | --debug-syms ] [ -g | --extern-only ]
633 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
634 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
635 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
636 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
637 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
638 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
639 [ --defined-only ] [-l | --line-numbers ]
640 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
643 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
644 If no object files are listed as arguments, @code{nm} assumes the file
647 For each symbol, @code{nm} shows:
651 The symbol value, in the radix selected by options (see below), or
652 hexadecimal by default.
655 The symbol type. At least the following types are used; others are, as
656 well, depending on the object file format. If lowercase, the symbol is
657 local; if uppercase, the symbol is global (external).
659 @c Some more detail on exactly what these symbol types are used for
663 The symbol's value is absolute, and will not be changed by further
667 The symbol is in the uninitialized data section (known as BSS).
670 The symbol is common. Common symbols are uninitialized data. When
671 linking, multiple common symbols may appear with the same name. If the
672 symbol is defined anywhere, the common symbols are treated as undefined
673 references. For more details on common symbols, see the discussion of
674 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
677 The symbol is in the initialized data section.
680 The symbol is in an initialized data section for small objects. Some
681 object file formats permit more efficient access to small data objects,
682 such as a global int variable as opposed to a large global array.
685 The symbol is an indirect reference to another symbol. This is a GNU
686 extension to the a.out object file format which is rarely used.
689 The symbol is a debugging symbol.
692 The symbol is in a read only data section.
695 The symbol is in an uninitialized data section for small objects.
698 The symbol is in the text (code) section.
701 The symbol is undefined.
704 The symbol is a weak object. When a weak defined symbol is linked with
705 a normal defined symbol, the normal defined symbol is used with no error.
706 When a weak undefined symbol is linked and the symbol is not defined,
707 the value of the weak symbol becomes zero with no error.
710 The symbol is a weak symbol that has not been specifically tagged as a
711 weak object symbol. When a weak defined symbol is linked with a normal
712 defined symbol, the normal defined symbol is used with no error.
713 When a weak undefined symbol is linked and the symbol is not defined,
714 the value of the weak symbol becomes zero with no error.
717 The symbol is a stabs symbol in an a.out object file. In this case, the
718 next values printed are the stabs other field, the stabs desc field, and
719 the stab type. Stabs symbols are used to hold debugging information;
720 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
721 ``stabs'' debug format}.
724 The symbol type is unknown, or object file format specific.
731 The long and short forms of options, shown here as alternatives, are
737 @itemx --print-file-name
738 @cindex input file name
740 @cindex source file name
741 Precede each symbol by the name of the input file (or archive member)
742 in which it was found, rather than identifying the input file once only,
743 before all of its symbols.
747 @cindex debugging symbols
748 Display all symbols, even debugger-only symbols; normally these are not
752 @cindex @code{nm} format
753 @cindex @code{nm} compatibility
754 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
758 @cindex demangling in nm
759 Decode (@dfn{demangle}) low-level symbol names into user-level names.
760 Besides removing any initial underscore prepended by the system, this
761 makes C++ function names readable. @xref{c++filt}, for more information
765 Do not demangle low-level symbol names. This is the default.
769 @cindex dynamic symbols
770 Display the dynamic symbols rather than the normal symbols. This is
771 only meaningful for dynamic objects, such as certain types of shared
774 @item -f @var{format}
775 @itemx --format=@var{format}
776 @cindex @code{nm} format
777 @cindex @code{nm} compatibility
778 Use the output format @var{format}, which can be @code{bsd},
779 @code{sysv}, or @code{posix}. The default is @code{bsd}.
780 Only the first character of @var{format} is significant; it can be
781 either upper or lower case.
785 @cindex external symbols
786 Display only external symbols.
789 @itemx --line-numbers
790 @cindex symbol line numbers
791 For each symbol, use debugging information to try to find a filename and
792 line number. For a defined symbol, look for the line number of the
793 address of the symbol. For an undefined symbol, look for the line
794 number of a relocation entry which refers to the symbol. If line number
795 information can be found, print it after the other symbol information.
799 @itemx --numeric-sort
800 Sort symbols numerically by their addresses, rather than alphabetically
805 @cindex sorting symbols
806 Do not bother to sort the symbols in any order; print them in the order
811 Use the POSIX.2 standard output format instead of the default format.
812 Equivalent to @samp{-f posix}.
816 @cindex symbol index, listing
817 When listing symbols from archive members, include the index: a mapping
818 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
819 contain definitions for which names.
822 @itemx --reverse-sort
823 Reverse the order of the sort (whether numeric or alphabetic); let the
827 Sort symbols by size. The size is computed as the difference between
828 the value of the symbol and the value of the symbol with the next higher
829 value. The size of the symbol is printed, rather than the value.
832 @itemx --radix=@var{radix}
833 Use @var{radix} as the radix for printing the symbol values. It must be
834 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
836 @item --target=@var{bfdname}
837 @cindex object code format
838 Specify an object code format other than your system's default format.
839 @xref{Target Selection}, for more information.
842 @itemx --undefined-only
843 @cindex external symbols
844 @cindex undefined symbols
845 Display only undefined symbols (those external to each object file).
848 @cindex external symbols
849 @cindex undefined symbols
850 Display only defined symbols for each object file.
854 Show the version number of @code{nm} and exit.
857 Show a summary of the options to @code{nm} and exit.
864 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
865 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
866 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
867 [ -S | --strip-all ] [ -g | --strip-debug ]
868 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
869 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
870 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
871 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
872 [ -x | --discard-all ] [ -X | --discard-locals ]
873 [ -b @var{byte} | --byte=@var{byte} ]
874 [ -i @var{interleave} | --interleave=@var{interleave} ]
875 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
876 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
877 [ -p | --preserve-dates ] [ --debugging ]
878 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
879 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
880 [ --change-addresses=@var{incr} ]
881 [ --change-section-address @var{section}@{=,+,-@}@var{val} ]
882 [ --change-section-lma @var{section}@{=,+,-@}@var{val} ]
883 [ --change-section-vma @var{section}@{=,+,-@}@var{val} ]
884 [ --change-warnings ] [ --no-change-warnings ]
885 [ --set-section-flags @var{section}=@var{flags} ]
886 [ --add-section @var{sectionname}=@var{filename} ]
887 [ --change-leading-char ] [ --remove-leading-char ]
888 [ --redefine-sym @var{old}=@var{new} ] [ --weaken ]
889 [ -v | --verbose ] [ -V | --version ] [ --help ]
890 @var{infile} [@var{outfile}]
893 The @sc{gnu} @code{objcopy} utility copies the contents of an object
894 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
895 read and write the object files. It can write the destination object
896 file in a format different from that of the source object file. The
897 exact behavior of @code{objcopy} is controlled by command-line options.
898 Note that @code{objcopy} should be able to copy a fully linked file
899 between any two formats. However, copying a relocatable object file
900 between any two formats may not work as expected.
902 @code{objcopy} creates temporary files to do its translations and
903 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
904 translation work; it has access to all the formats described in @sc{bfd}
905 and thus is able to recognize most formats without being told
906 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
908 @code{objcopy} can be used to generate S-records by using an output
909 target of @samp{srec} (e.g., use @samp{-O srec}).
911 @code{objcopy} can be used to generate a raw binary file by using an
912 output target of @samp{binary} (e.g., use @samp{-O binary}). When
913 @code{objcopy} generates a raw binary file, it will essentially produce
914 a memory dump of the contents of the input object file. All symbols and
915 relocation information will be discarded. The memory dump will start at
916 the load address of the lowest section copied into the output file.
918 When generating an S-record or a raw binary file, it may be helpful to
919 use @samp{-S} to remove sections containing debugging information. In
920 some cases @samp{-R} will be useful to remove sections which contain
921 information that is not needed by the binary file.
926 The input and output files, respectively.
927 If you do not specify @var{outfile}, @code{objcopy} creates a
928 temporary file and destructively renames the result with
929 the name of @var{infile}.
931 @item -I @var{bfdname}
932 @itemx --input-target=@var{bfdname}
933 Consider the source file's object format to be @var{bfdname}, rather than
934 attempting to deduce it. @xref{Target Selection}, for more information.
936 @item -O @var{bfdname}
937 @itemx --output-target=@var{bfdname}
938 Write the output file using the object format @var{bfdname}.
939 @xref{Target Selection}, for more information.
941 @item -F @var{bfdname}
942 @itemx --target=@var{bfdname}
943 Use @var{bfdname} as the object format for both the input and the output
944 file; i.e., simply transfer data from source to destination with no
945 translation. @xref{Target Selection}, for more information.
947 @item -j @var{sectionname}
948 @itemx --only-section=@var{sectionname}
949 Copy only the named section from the input file to the output file.
950 This option may be given more than once. Note that using this option
951 inappropriately may make the output file unusable.
953 @item -R @var{sectionname}
954 @itemx --remove-section=@var{sectionname}
955 Remove any section named @var{sectionname} from the output file. This
956 option may be given more than once. Note that using this option
957 inappropriately may make the output file unusable.
961 Do not copy relocation and symbol information from the source file.
965 Do not copy debugging symbols from the source file.
967 @item --strip-unneeded
968 Strip all symbols that are not needed for relocation processing.
970 @item -K @var{symbolname}
971 @itemx --keep-symbol=@var{symbolname}
972 Copy only symbol @var{symbolname} from the source file. This option may
973 be given more than once.
975 @item -N @var{symbolname}
976 @itemx --strip-symbol=@var{symbolname}
977 Do not copy symbol @var{symbolname} from the source file. This option
978 may be given more than once.
980 @item -L @var{symbolname}
981 @itemx --localize-symbol=@var{symbolname}
982 Make symbol @var{symbolname} local to the file, so that it is not
983 visible externally. This option may be given more than once.
985 @item -W @var{symbolname}
986 @itemx --weaken-symbol=@var{symbolname}
987 Make symbol @var{symbolname} weak. This option may be given more than once.
991 Do not copy non-global symbols from the source file.
992 @c FIXME any reason to prefer "non-global" to "local" here?
995 @itemx --discard-locals
996 Do not copy compiler-generated local symbols.
997 (These usually start with @samp{L} or @samp{.}.)
1000 @itemx --byte=@var{byte}
1001 Keep only every @var{byte}th byte of the input file (header data is not
1002 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1003 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
1004 option, or the default of 4. This option is useful for creating files
1005 to program @sc{rom}. It is typically used with an @code{srec} output
1008 @item -i @var{interleave}
1009 @itemx --interleave=@var{interleave}
1010 Only copy one out of every @var{interleave} bytes. Select which byte to
1011 copy with the @var{-b} or @samp{--byte} option. The default is 4.
1012 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
1016 @itemx --preserve-dates
1017 Set the access and modification dates of the output file to be the same
1018 as those of the input file.
1021 Convert debugging information, if possible. This is not the default
1022 because only certain debugging formats are supported, and the
1023 conversion process can be time consuming.
1025 @item --gap-fill @var{val}
1026 Fill gaps between sections with @var{val}. This operation applies to
1027 the @emph{load address} (LMA) of the sections. It is done by increasing
1028 the size of the section with the lower address, and filling in the extra
1029 space created with @var{val}.
1031 @item --pad-to @var{address}
1032 Pad the output file up to the load address @var{address}. This is
1033 done by increasing the size of the last section. The extra space is
1034 filled in with the value specified by @samp{--gap-fill} (default zero).
1036 @item --set-start @var{val}
1037 Set the start address of the new file to @var{val}. Not all object file
1038 formats support setting the start address.
1040 @item --change-start @var{incr}
1041 @itemx --adjust-start @var{incr}
1042 @cindex changing start address
1043 Change the start address by adding @var{incr}. Not all object file
1044 formats support setting the start address.
1046 @item --change-addresses @var{incr}
1047 @itemx --adjust-vma @var{incr}
1048 @cindex changing object addresses
1049 Change the VMA and LMA addresses of all sections, as well as the start
1050 address, by adding @var{incr}. Some object file formats do not permit
1051 section addresses to be changed arbitrarily. Note that this does not
1052 relocate the sections; if the program expects sections to be loaded at a
1053 certain address, and this option is used to change the sections such
1054 that they are loaded at a different address, the program may fail.
1056 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1057 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1058 @cindex changing section address
1059 Set or change both the VMA address and the LMA address of the named
1060 @var{section}. If @samp{=} is used, the section address is set to
1061 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1062 section address. See the comments under @samp{--change-addresses},
1063 above. If @var{section} does not exist in the input file, a warning will
1064 be issued, unless @samp{--no-change-warnings} is used.
1066 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1067 @cindex changing section LMA
1068 Set or change the LMA address of the named @var{section}. The LMA
1069 address is the address where the section will be loaded into memory at
1070 program load time. Normally this is the same as the VMA address, which
1071 is the address of the section at program run time, but on some systems,
1072 especially those where a program is held in ROM, the two can be
1073 different. If @samp{=} is used, the section address is set to
1074 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1075 section address. See the comments under @samp{--change-addresses},
1076 above. If @var{section} does not exist in the input file, a warning
1077 will be issued, unless @samp{--no-change-warnings} is used.
1079 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1080 @cindex changing section VMA
1081 Set or change the VMA address of the named @var{section}. The VMA
1082 address is the address where the section will be located once the
1083 program has started executing. Normally this is the same as the LMA
1084 address, which is the address where the section will be loaded into
1085 memory, but on some systems, especially those where a program is held in
1086 ROM, the two can be different. If @samp{=} is used, the section address
1087 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1088 from the section address. See the comments under
1089 @samp{--change-addresses}, above. If @var{section} does not exist in
1090 the input file, a warning will be issued, unless
1091 @samp{--no-change-warnings} is used.
1093 @item --change-warnings
1094 @itemx --adjust-warnings
1095 If @samp{--change-section-address} or @samp{--change-section-lma} or
1096 @samp{--change-section-vma} is used, and the named section does not
1097 exist, issue a warning. This is the default.
1099 @item --no-change-warnings
1100 @itemx --no-adjust-warnings
1101 Do not issue a warning if @samp{--change-section-address} or
1102 @samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1103 if the named section does not exist.
1105 @item --set-section-flags @var{section}=@var{flags}
1106 Set the flags for the named section. The @var{flags} argument is a
1107 comma separated string of flag names. The recognized names are
1108 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1109 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1110 @samp{debug}. You can set the @samp{contents} flag for a section which
1111 does not have contents, but it is not meaningful to clear the
1112 @samp{contents} flag of a section which does have contents--just remove
1113 the section instead. Not all flags are meaningful for all object file
1116 @item --add-section @var{sectionname}=@var{filename}
1117 Add a new section named @var{sectionname} while copying the file. The
1118 contents of the new section are taken from the file @var{filename}. The
1119 size of the section will be the size of the file. This option only
1120 works on file formats which can support sections with arbitrary names.
1122 @item --change-leading-char
1123 Some object file formats use special characters at the start of
1124 symbols. The most common such character is underscore, which compilers
1125 often add before every symbol. This option tells @code{objcopy} to
1126 change the leading character of every symbol when it converts between
1127 object file formats. If the object file formats use the same leading
1128 character, this option has no effect. Otherwise, it will add a
1129 character, or remove a character, or change a character, as
1132 @item --remove-leading-char
1133 If the first character of a global symbol is a special symbol leading
1134 character used by the object file format, remove the character. The
1135 most common symbol leading character is underscore. This option will
1136 remove a leading underscore from all global symbols. This can be useful
1137 if you want to link together objects of different file formats with
1138 different conventions for symbol names. This is different from
1139 @code{--change-leading-char} because it always changes the symbol name
1140 when appropriate, regardless of the object file format of the output
1143 @item --redefine-sym @var{old}=@var{new}
1144 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1145 when one is trying link two things together for which you have no
1146 source, and there are name collisions.
1149 Change all global symbols in the file to be weak. This can be useful
1150 when building an object which will be linked against other objects using
1151 the @code{-R} option to the linker. This option is only effective when
1152 using an object file format which supports weak symbols.
1156 Show the version number of @code{objcopy}.
1160 Verbose output: list all object files modified. In the case of
1161 archives, @samp{objcopy -V} lists all members of the archive.
1164 Show a summary of the options to @code{objcopy}.
1170 @cindex object file information
1174 objdump [ -a | --archive-headers ]
1175 [ -b @var{bfdname} | --target=@var{bfdname} ]
1177 [ -d | --disassemble ]
1178 [ -D | --disassemble-all ]
1179 [ -z | --disassemble-zeroes ]
1180 [ -EB | -EL | --endian=@{big | little @} ]
1181 [ -f | --file-headers ]
1182 [ --file-start-context ]
1183 [ -g | --debugging ]
1184 [ -h | --section-headers | --headers ]
1186 [ -j @var{section} | --section=@var{section} ]
1187 [ -l | --line-numbers ]
1189 [ -m @var{machine} | --architecture=@var{machine} ]
1190 [ -M @var{options} | --disassembler-options=@var{options}]
1191 [ -p | --private-headers ]
1193 [ -R | --dynamic-reloc ]
1194 [ -s | --full-contents ]
1197 [ -T | --dynamic-syms ]
1198 [ -x | --all-headers ]
1200 [ --start-address=@var{address} ]
1201 [ --stop-address=@var{address} ]
1202 [ --prefix-addresses]
1203 [ --[no-]show-raw-insn ]
1204 [ --adjust-vma=@var{offset} ]
1207 @var{objfile}@dots{}
1210 @code{objdump} displays information about one or more object files.
1211 The options control what particular information to display. This
1212 information is mostly useful to programmers who are working on the
1213 compilation tools, as opposed to programmers who just want their
1214 program to compile and work.
1216 @var{objfile}@dots{} are the object files to be examined. When you
1217 specify archives, @code{objdump} shows information on each of the member
1220 The long and short forms of options, shown here as alternatives, are
1221 equivalent. At least one option from the list
1222 @samp{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given.
1226 @itemx --archive-header
1227 @cindex archive headers
1228 If any of the @var{objfile} files are archives, display the archive
1229 header information (in a format similar to @samp{ls -l}). Besides the
1230 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1231 the object file format of each archive member.
1233 @item --adjust-vma=@var{offset}
1234 @cindex section addresses in objdump
1235 @cindex VMA in objdump
1236 When dumping information, first add @var{offset} to all the section
1237 addresses. This is useful if the section addresses do not correspond to
1238 the symbol table, which can happen when putting sections at particular
1239 addresses when using a format which can not represent section addresses,
1242 @item -b @var{bfdname}
1243 @itemx --target=@var{bfdname}
1244 @cindex object code format
1245 Specify that the object-code format for the object files is
1246 @var{bfdname}. This option may not be necessary; @var{objdump} can
1247 automatically recognize many formats.
1251 objdump -b oasys -m vax -h fu.o
1254 displays summary information from the section headers (@samp{-h}) of
1255 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1256 file in the format produced by Oasys compilers. You can list the
1257 formats available with the @samp{-i} option.
1258 @xref{Target Selection}, for more information.
1262 @cindex demangling in objdump
1263 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1264 Besides removing any initial underscore prepended by the system, this
1265 makes C++ function names readable. @xref{c++filt}, for more information
1270 Display debugging information. This attempts to parse debugging
1271 information stored in the file and print it out using a C like syntax.
1272 Only certain types of debugging information have been implemented.
1275 @itemx --disassemble
1276 @cindex disassembling object code
1277 @cindex machine instructions
1278 Display the assembler mnemonics for the machine instructions from
1279 @var{objfile}. This option only disassembles those sections which are
1280 expected to contain instructions.
1283 @itemx --disassemble-all
1284 Like @samp{-d}, but disassemble the contents of all sections, not just
1285 those expected to contain instructions.
1287 @item --prefix-addresses
1288 When disassembling, print the complete address on each line. This is
1289 the older disassembly format.
1291 @item --disassemble-zeroes
1292 Normally the disassembly output will skip blocks of zeroes. This
1293 option directs the disassembler to disassemble those blocks, just like
1298 @itemx --endian=@{big|little@}
1300 @cindex disassembly endianness
1301 Specify the endianness of the object files. This only affects
1302 disassembly. This can be useful when disassembling a file format which
1303 does not describe endianness information, such as S-records.
1306 @itemx --file-header
1307 @cindex object file header
1308 Display summary information from the overall header of
1309 each of the @var{objfile} files.
1311 @item --file-start-context
1312 @cindex source code context
1313 Specify that when displaying interlisted source code/disassembly
1314 (assumes '-S') from a file that has not yet been displayed, extend the
1315 context to the start of the file.
1318 @itemx --section-header
1320 @cindex section headers
1321 Display summary information from the section headers of the
1324 File segments may be relocated to nonstandard addresses, for example by
1325 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1326 @code{ld}. However, some object file formats, such as a.out, do not
1327 store the starting address of the file segments. In those situations,
1328 although @code{ld} relocates the sections correctly, using @samp{objdump
1329 -h} to list the file section headers cannot show the correct addresses.
1330 Instead, it shows the usual addresses, which are implicit for the
1334 Print a summary of the options to @code{objdump} and exit.
1338 @cindex architectures available
1339 @cindex object formats available
1340 Display a list showing all architectures and object formats available
1341 for specification with @samp{-b} or @samp{-m}.
1344 @itemx --section=@var{name}
1345 @cindex section information
1346 Display information only for section @var{name}.
1349 @itemx --line-numbers
1350 @cindex source filenames for object files
1351 Label the display (using debugging information) with the filename and
1352 source line numbers corresponding to the object code or relocs shown.
1353 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1355 @item -m @var{machine}
1356 @itemx --architecture=@var{machine}
1357 @cindex architecture
1358 @cindex disassembly architecture
1359 Specify the architecture to use when disassembling object files. This
1360 can be useful when disassembling object files which do not describe
1361 architecture information, such as S-records. You can list the available
1362 architectures with the @samp{-i} option.
1364 @item -M @var{options}
1365 @itemx --disassembler-options=@var{options}
1366 Pass target specific information to the disassembler. Only supported on
1369 If the target is an ARM architecture then this switch can be used to
1370 select which register name set is used during disassembler. Specifying
1371 @samp{-M reg-name-std} (the default) will select the register names as
1372 used in ARM's instruction set documentation, but with register 13 called
1373 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1374 @samp{-M reg-names-apcs} will select the name set used by the ARM
1375 Procedure Call Standard, whilst specifying @samp{-M reg-names-raw} will
1376 just use @samp{r} followed by the register number.
1378 There are also two variants on the APCS register naming scheme enabled
1379 by @samp{-M reg-names-atpcs} and @samp{-M reg-names-special-atpcs} which
1380 use the ARM/Thumb Procedure Call Standard naming conventions. (Eiuther
1381 with the normal register name sor the special register names).
1383 This option can also be used for ARM architectures to force the
1384 disassembler to interpret all instructions as THUMB instructions by
1385 using the switch @samp{--disassembler-options=force-thumb}. This can be
1386 useful when attempting to disassemble thumb code produced by other
1390 @itemx --private-headers
1391 Print information that is specific to the object file format. The exact
1392 information printed depends upon the object file format. For some
1393 object file formats, no additional information is printed.
1397 @cindex relocation entries, in object file
1398 Print the relocation entries of the file. If used with @samp{-d} or
1399 @samp{-D}, the relocations are printed interspersed with the
1403 @itemx --dynamic-reloc
1404 @cindex dynamic relocation entries, in object file
1405 Print the dynamic relocation entries of the file. This is only
1406 meaningful for dynamic objects, such as certain types of shared
1410 @itemx --full-contents
1411 @cindex sections, full contents
1412 @cindex object file sections
1413 Display the full contents of any sections requested.
1417 @cindex source disassembly
1418 @cindex disassembly, with source
1419 Display source code intermixed with disassembly, if possible. Implies
1422 @item --show-raw-insn
1423 When disassembling instructions, print the instruction in hex as well as
1424 in symbolic form. This is the default except when
1425 @code{--prefix-addresses} is used.
1427 @item --no-show-raw-insn
1428 When disassembling instructions, do not print the instruction bytes.
1429 This is the default when @code{--prefix-addresses} is used.
1435 @cindex debug symbols
1436 @cindex ELF object file format
1437 Display the full contents of any sections requested. Display the
1438 contents of the .stab and .stab.index and .stab.excl sections from an
1439 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1440 @code{.stab} debugging symbol-table entries are carried in an ELF
1441 section. In most other file formats, debugging symbol-table entries are
1442 interleaved with linkage symbols, and are visible in the @samp{--syms}
1443 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1444 Overview,stabs.info, The ``stabs'' debug format}.
1446 @item --start-address=@var{address}
1447 @cindex start-address
1448 Start displaying data at the specified address. This affects the output
1449 of the @code{-d}, @code{-r} and @code{-s} options.
1451 @item --stop-address=@var{address}
1452 @cindex stop-address
1453 Stop displaying data at the specified address. This affects the output
1454 of the @code{-d}, @code{-r} and @code{-s} options.
1458 @cindex symbol table entries, printing
1459 Print the symbol table entries of the file.
1460 This is similar to the information provided by the @samp{nm} program.
1463 @itemx --dynamic-syms
1464 @cindex dynamic symbol table entries, printing
1465 Print the dynamic symbol table entries of the file. This is only
1466 meaningful for dynamic objects, such as certain types of shared
1467 libraries. This is similar to the information provided by the @samp{nm}
1468 program when given the @samp{-D} (@samp{--dynamic}) option.
1471 Print the version number of @code{objdump} and exit.
1475 @cindex all header information, object file
1476 @cindex header information, all
1477 Display all available header information, including the symbol table and
1478 relocation entries. Using @samp{-x} is equivalent to specifying all of
1479 @samp{-a -f -h -r -t}.
1483 @cindex wide output, printing
1484 Format some lines for output devices that have more than 80 columns.
1491 @cindex archive contents
1492 @cindex symbol index
1495 ranlib [-vV] @var{archive}
1498 @code{ranlib} generates an index to the contents of an archive and
1499 stores it in the archive. The index lists each symbol defined by a
1500 member of an archive that is a relocatable object file.
1502 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1504 An archive with such an index speeds up linking to the library and
1505 allows routines in the library to call each other without regard to
1506 their placement in the archive.
1508 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1509 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1516 Show the version number of @code{ranlib}.
1523 @cindex section sizes
1526 size [ -A | -B | --format=@var{compatibility} ]
1527 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1528 [ --target=@var{bfdname} ] [ -V | --version ]
1529 [ @var{objfile}@dots{} ]
1532 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1533 size---for each of the object or archive files @var{objfile} in its
1534 argument list. By default, one line of output is generated for each
1535 object file or each module in an archive.
1537 @var{objfile}@dots{} are the object files to be examined.
1538 If none are specified, the file @code{a.out} will be used.
1540 The command line options have the following meanings:
1545 @itemx --format=@var{compatibility}
1546 @cindex @code{size} display format
1547 Using one of these options, you can choose whether the output from @sc{gnu}
1548 @code{size} resembles output from System V @code{size} (using @samp{-A},
1549 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1550 @samp{--format=berkeley}). The default is the one-line format similar to
1552 @c Bonus for doc-source readers: you can also say --format=strange (or
1553 @c anything else that starts with 's') for sysv, and --format=boring (or
1554 @c anything else that starts with 'b') for Berkeley.
1556 Here is an example of the Berkeley (default) format of output from
1559 $ size --format=Berkeley ranlib size
1560 text data bss dec hex filename
1561 294880 81920 11592 388392 5ed28 ranlib
1562 294880 81920 11888 388688 5ee50 size
1566 This is the same data, but displayed closer to System V conventions:
1569 $ size --format=SysV ranlib size
1587 Show a summary of acceptable arguments and options.
1592 @itemx --radix=@var{number}
1593 @cindex @code{size} number format
1594 @cindex radix for section sizes
1595 Using one of these options, you can control whether the size of each
1596 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1597 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1598 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1599 values (8, 10, 16) are supported. The total size is always given in two
1600 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1601 octal and hexadecimal if you're using @samp{-o}.
1603 @item --target=@var{bfdname}
1604 @cindex object code format
1605 Specify that the object-code format for @var{objfile} is
1606 @var{bfdname}. This option may not be necessary; @code{size} can
1607 automatically recognize many formats.
1608 @xref{Target Selection}, for more information.
1612 Display the version number of @code{size}.
1618 @cindex listings strings
1619 @cindex printing strings
1620 @cindex strings, printing
1623 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1624 [--all] [--print-file-name] [--bytes=@var{min-len}]
1625 [--radix=@var{radix}] [--target=@var{bfdname}]
1626 [--help] [--version] @var{file}@dots{}
1629 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1630 character sequences that are at least 4 characters long (or the number
1631 given with the options below) and are followed by an unprintable
1632 character. By default, it only prints the strings from the initialized
1633 and loaded sections of object files; for other types of files, it prints
1634 the strings from the whole file.
1636 @code{strings} is mainly useful for determining the contents of non-text
1643 Do not scan only the initialized and loaded sections of object files;
1644 scan the whole files.
1647 @itemx --print-file-name
1648 Print the name of the file before each string.
1651 Print a summary of the program usage on the standard output and exit.
1653 @item -@var{min-len}
1654 @itemx -n @var{min-len}
1655 @itemx --bytes=@var{min-len}
1656 Print sequences of characters that are at least @var{min-len} characters
1657 long, instead of the default 4.
1660 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1661 act like @samp{-t d} instead. Since we can not be compatible with both
1662 ways, we simply chose one.
1664 @item -t @var{radix}
1665 @itemx --radix=@var{radix}
1666 Print the offset within the file before each string. The single
1667 character argument specifies the radix of the offset---@samp{o} for
1668 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1670 @item --target=@var{bfdname}
1671 @cindex object code format
1672 Specify an object code format other than your system's default format.
1673 @xref{Target Selection}, for more information.
1677 Print the program version number on the standard output and exit.
1684 @cindex removing symbols
1685 @cindex discarding symbols
1686 @cindex symbols, discarding
1689 strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1690 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1691 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1692 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1693 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1694 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1695 [ -x | --discard-all ] [ -X | --discard-locals ]
1696 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1697 [ -o @var{file} ] [ -p | --preserve-dates ]
1698 [ -v | --verbose ] [ -V | --version ] [ --help ]
1699 @var{objfile}@dots{}
1702 @sc{gnu} @code{strip} discards all symbols from object files
1703 @var{objfile}. The list of object files may include archives.
1704 At least one object file must be given.
1706 @code{strip} modifies the files named in its argument,
1707 rather than writing modified copies under different names.
1710 @item -F @var{bfdname}
1711 @itemx --target=@var{bfdname}
1712 Treat the original @var{objfile} as a file with the object
1713 code format @var{bfdname}, and rewrite it in the same format.
1714 @xref{Target Selection}, for more information.
1717 Show a summary of the options to @code{strip} and exit.
1719 @item -I @var{bfdname}
1720 @itemx --input-target=@var{bfdname}
1721 Treat the original @var{objfile} as a file with the object
1722 code format @var{bfdname}.
1723 @xref{Target Selection}, for more information.
1725 @item -O @var{bfdname}
1726 @itemx --output-target=@var{bfdname}
1727 Replace @var{objfile} with a file in the output format @var{bfdname}.
1728 @xref{Target Selection}, for more information.
1730 @item -R @var{sectionname}
1731 @itemx --remove-section=@var{sectionname}
1732 Remove any section named @var{sectionname} from the output file. This
1733 option may be given more than once. Note that using this option
1734 inappropriately may make the output file unusable.
1742 @itemx --strip-debug
1743 Remove debugging symbols only.
1745 @item --strip-unneeded
1746 Remove all symbols that are not needed for relocation processing.
1748 @item -K @var{symbolname}
1749 @itemx --keep-symbol=@var{symbolname}
1750 Keep only symbol @var{symbolname} from the source file. This option may
1751 be given more than once.
1753 @item -N @var{symbolname}
1754 @itemx --strip-symbol=@var{symbolname}
1755 Remove symbol @var{symbolname} from the source file. This option may be
1756 given more than once, and may be combined with strip options other than
1760 Put the stripped output in @var{file}, rather than replacing the
1761 existing file. When this argument is used, only one @var{objfile}
1762 argument may be specified.
1765 @itemx --preserve-dates
1766 Preserve the access and modification dates of the file.
1769 @itemx --discard-all
1770 Remove non-global symbols.
1773 @itemx --discard-locals
1774 Remove compiler-generated local symbols.
1775 (These usually start with @samp{L} or @samp{.}.)
1779 Show the version number for @code{strip}.
1783 Verbose output: list all object files modified. In the case of
1784 archives, @samp{strip -v} lists all members of the archive.
1787 @node c++filt, addr2line, strip, Top
1791 @cindex demangling C++ symbols
1794 c++filt [ -_ | --strip-underscores ]
1796 [ -n | --no-strip-underscores ]
1797 [ -s @var{format} | --format=@var{format} ]
1798 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1802 The C++ and Java languages provides function overloading, which means
1803 that you can write many functions with the same name (providing each
1804 takes parameters of different types). All C++ and Java function names
1805 are encoded into a low-level assembly label (this process is known as
1806 @dfn{mangling}). The @code{c++filt}
1807 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1808 MS-DOS this program is named @code{cxxfilt}.}
1809 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1810 names into user-level names so that the linker can keep these overloaded
1811 functions from clashing.
1813 Every alphanumeric word (consisting of letters, digits, underscores,
1814 dollars, or periods) seen in the input is a potential label. If the
1815 label decodes into a C++ name, the C++ name replaces the low-level
1818 You can use @code{c++filt} to decipher individual symbols:
1821 c++filt @var{symbol}
1824 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1825 names from the standard input and writes the demangled names to the
1826 standard output. All results are printed on the standard output.
1830 @itemx --strip-underscores
1831 On some systems, both the C and C++ compilers put an underscore in front
1832 of every name. For example, the C name @code{foo} gets the low-level
1833 name @code{_foo}. This option removes the initial underscore. Whether
1834 @code{c++filt} removes the underscore by default is target dependent.
1838 Prints demangled names using Java syntax. The default is to use C++
1842 @itemx --no-strip-underscores
1843 Do not remove the initial underscore.
1845 @item -s @var{format}
1846 @itemx --format=@var{format}
1847 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1848 different C++ compilers. The argument to this option selects which
1853 the one used by the @sc{gnu} compiler (the default method)
1855 the one used by the Lucid compiler
1857 the one specified by the C++ Annotated Reference Manual
1859 the one used by the HP compiler
1861 the one used by the EDG compiler
1865 Print a summary of the options to @code{c++filt} and exit.
1868 Print the version number of @code{c++filt} and exit.
1872 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1873 user interface are subject to change in future releases. In particular,
1874 a command-line option may be required in the the future to decode a name
1875 passed as an argument on the command line; in other words,
1878 c++filt @var{symbol}
1882 may in a future release become
1885 c++filt @var{option} @var{symbol}
1893 @cindex address to file name and line number
1896 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1898 [ -e @var{filename} | --exe=@var{filename} ]
1899 [ -f | --functions ] [ -s | --basename ]
1900 [ -H | --help ] [ -V | --version ]
1904 @code{addr2line} translates program addresses into file names and line
1905 numbers. Given an address and an executable, it uses the debugging
1906 information in the executable to figure out which file name and line
1907 number are associated with a given address.
1909 The executable to use is specified with the @code{-e} option. The
1910 default is the file @file{a.out}.
1912 @code{addr2line} has two modes of operation.
1914 In the first, hexadecimal addresses are specified on the command line,
1915 and @code{addr2line} displays the file name and line number for each
1918 In the second, @code{addr2line} reads hexadecimal addresses from
1919 standard input, and prints the file name and line number for each
1920 address on standard output. In this mode, @code{addr2line} may be used
1921 in a pipe to convert dynamically chosen addresses.
1923 The format of the output is @samp{FILENAME:LINENO}. The file name and
1924 line number for each address is printed on a separate line. If the
1925 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1926 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1927 containing the address.
1929 If the file name or function name can not be determined,
1930 @code{addr2line} will print two question marks in their place. If the
1931 line number can not be determined, @code{addr2line} will print 0.
1933 The long and short forms of options, shown here as alternatives, are
1937 @item -b @var{bfdname}
1938 @itemx --target=@var{bfdname}
1939 @cindex object code format
1940 Specify that the object-code format for the object files is
1945 @cindex demangling in objdump
1946 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1947 Besides removing any initial underscore prepended by the system, this
1948 makes C++ function names readable. @xref{c++filt}, for more information
1951 @item -e @var{filename}
1952 @itemx --exe=@var{filename}
1953 Specify the name of the executable for which addresses should be
1954 translated. The default file is @file{a.out}.
1958 Display function names as well as file and line number information.
1962 Display only the base of each file name.
1968 @code{nlmconv} converts a relocatable object file into a NetWare
1972 @code{nlmconv} currently works with @samp{i386} object
1973 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1974 object files in @sc{elf}, or @code{a.out} format@footnote{
1975 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1976 format in the Binary File Descriptor library. It has only been tested
1977 with the above formats.}.
1981 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1982 utilities, since it is only useful for NLM targets.
1986 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1987 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1988 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1989 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1990 [ -h | --help ] [ -V | --version ]
1991 @var{infile} @var{outfile}
1994 @code{nlmconv} converts the relocatable @samp{i386} object file
1995 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1996 reading @var{headerfile} for NLM header information. For instructions
1997 on writing the NLM command file language used in header files, see the
1998 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1999 Development and Tools Overview}, which is part of the NLM Software
2000 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2001 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2002 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
2005 @code{nlmconv} can perform a link step. In other words, you can list
2006 more than one object file for input if you list them in the definitions
2007 file (rather than simply specifying one input file on the command line).
2008 In this case, @code{nlmconv} calls the linker for you.
2011 @item -I @var{bfdname}
2012 @itemx --input-target=@var{bfdname}
2013 Object format of the input file. @code{nlmconv} can usually determine
2014 the format of a given file (so no default is necessary).
2015 @xref{Target Selection}, for more information.
2017 @item -O @var{bfdname}
2018 @itemx --output-target=@var{bfdname}
2019 Object format of the output file. @code{nlmconv} infers the output
2020 format based on the input format, e.g. for a @samp{i386} input file the
2021 output format is @samp{nlm32-i386}.
2022 @xref{Target Selection}, for more information.
2024 @item -T @var{headerfile}
2025 @itemx --header-file=@var{headerfile}
2026 Reads @var{headerfile} for NLM header information. For instructions on
2027 writing the NLM command file language used in header files, see@ see the
2028 @samp{linkers} section, of the @cite{NLM Development and Tools
2029 Overview}, which is part of the NLM Software Developer's Kit, available
2034 Displays (on standard error) the linker command line used by @code{nlmconv}.
2036 @item -l @var{linker}
2037 @itemx --linker=@var{linker}
2038 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2043 Prints a usage summary.
2047 Prints the version number for @code{nlmconv}.
2053 @code{windres} may be used to manipulate Windows resources.
2056 @emph{Warning:} @code{windres} is not always built as part of the binary
2057 utilities, since it is only useful for Windows targets.
2061 windres [options] [input-file] [output-file]
2064 @code{windres} reads resources from an input file and copies them into
2065 an output file. Either file may be in one of three formats:
2069 A text format read by the Resource Compiler.
2072 A binary format generated by the Resource Compiler.
2075 A COFF object or executable.
2078 The exact description of these different formats is available in
2079 documentation from Microsoft.
2081 When @code{windres} converts from the @code{rc} format to the @code{res}
2082 format, it is acting like the Windows Resource Compiler. When
2083 @code{windres} converts from the @code{res} format to the @code{coff}
2084 format, it is acting like the Windows @code{CVTRES} program.
2086 When @code{windres} generates an @code{rc} file, the output is similar
2087 but not identical to the format expected for the input. When an input
2088 @code{rc} file refers to an external filename, an output @code{rc} file
2089 will instead include the file contents.
2091 If the input or output format is not specified, @code{windres} will
2092 guess based on the file name, or, for the input file, the file contents.
2093 A file with an extension of @file{.rc} will be treated as an @code{rc}
2094 file, a file with an extension of @file{.res} will be treated as a
2095 @code{res} file, and a file with an extension of @file{.o} or
2096 @file{.exe} will be treated as a @code{coff} file.
2098 If no output file is specified, @code{windres} will print the resources
2099 in @code{rc} format to standard output.
2101 The normal use is for you to write an @code{rc} file, use @code{windres}
2102 to convert it to a COFF object file, and then link the COFF file into
2103 your application. This will make the resources described in the
2104 @code{rc} file available to Windows.
2107 @item -i @var{filename}
2108 @itemx --input @var{filename}
2109 The name of the input file. If this option is not used, then
2110 @code{windres} will use the first non-option argument as the input file
2111 name. If there are no non-option arguments, then @code{windres} will
2112 read from standard input. @code{windres} can not read a COFF file from
2115 @item -o @var{filename}
2116 @itemx --output @var{filename}
2117 The name of the output file. If this option is not used, then
2118 @code{windres} will use the first non-option argument, after any used
2119 for the input file name, as the output file name. If there is no
2120 non-option argument, then @code{windres} will write to standard output.
2121 @code{windres} can not write a COFF file to standard output.
2123 @item -I @var{format}
2124 @itemx --input-format @var{format}
2125 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2126 @samp{coff}. If no input format is specified, @code{windres} will
2127 guess, as described above.
2129 @item -O @var{format}
2130 @itemx --output-format @var{format}
2131 The output format to generate. @var{format} may be @samp{res},
2132 @samp{rc}, or @samp{coff}. If no output format is specified,
2133 @code{windres} will guess, as described above.
2135 @item -F @var{target}
2136 @itemx --target @var{target}
2137 Specify the BFD format to use for a COFF file as input or output. This
2138 is a BFD target name; you can use the @code{--help} option to see a list
2139 of supported targets. Normally @code{windres} will use the default
2140 format, which is the first one listed by the @code{--help} option.
2141 @ref{Target Selection}.
2143 @item --preprocessor @var{program}
2144 When @code{windres} reads an @code{rc} file, it runs it through the C
2145 preprocessor first. This option may be used to specify the preprocessor
2146 to use, including any leading arguments. The default preprocessor
2147 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2149 @item --include-dir @var{directory}
2150 Specify an include directory to use when reading an @code{rc} file.
2151 @code{windres} will pass this to the preprocessor as an @code{-I}
2152 option. @code{windres} will also search this directory when looking for
2153 files named in the @code{rc} file.
2155 @item -D @var{target}
2156 @itemx --define @var{sym}[=@var{val}]
2157 Specify a @code{-D} option to pass to the preprocessor when reading an
2161 Enable verbose mode. This tells you what the preprocessor is if you
2164 @item --language @var{val}
2165 Specify the default language to use when reading an @code{rc} file.
2166 @var{val} should be a hexadecimal language code. The low eight bits are
2167 the language, and the high eight bits are the sublanguage.
2169 @item --use-temp-file
2170 Use a temporary file to instead of using popen to read the output of
2171 the preprocessor. Use this option if the popen implementation is buggy
2172 on the host (eg., certain non-English language versions of Windows 95 and
2173 Windows 98 are known to have buggy popen where the output will instead
2176 @item --no-use-temp-file
2177 Use popen, not a temporary file, to read the output of the preprocessor.
2178 This is the default behaviour.
2181 Prints a usage summary.
2184 Prints the version number for @code{windres}.
2187 If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2188 this will turn on parser debugging.
2193 @chapter Create files needed to build and use DLLs
2197 @code{dlltool} may be used to create the files needed to build and use
2198 dynamic link libraries (DLLs).
2201 @emph{Warning:} @code{dlltool} is not always built as part of the binary
2202 utilities, since it is only useful for those targets which support DLLs.
2206 dlltool [-d|--input-def @var{def-file-name}]
2207 [-b|--base-file @var{base-file-name}]
2208 [-e|--output-exp @var{exports-file-name}]
2209 [-z|--output-def @var{def-file-name}]
2210 [-l|--output-lib @var{library-file-name}]
2211 [--export-all-symbols] [--no-export-all-symbols]
2212 [--exclude-symbols @var{list}]
2213 [--no-default-excludes]
2214 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2215 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2216 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2217 [-A|--add-stdcall-alias]
2218 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2219 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2220 [object-file @dots{}]
2223 @code{dlltool} reads its inputs, which can come from the @samp{-d} and
2224 @samp{-b} options as well as object files specified on the command
2225 line. It then processes these inputs and if the @samp{-e} option has
2226 been specified it creates a exports file. If the @samp{-l} option
2227 has been specified it creates a library file and if the @samp{-z} option
2228 has been specified it creates a def file. Any or all of the -e, -l
2229 and -z options can be present in one invocation of dlltool.
2231 When creating a DLL, along with the source for the DLL, it is necessary
2232 to have three other files. @code{dlltool} can help with the creation of
2235 The first file is a @samp{.def} file which specifies which functions are
2236 exported from the DLL, which functions the DLL imports, and so on. This
2237 is a text file and can be created by hand, or @code{dlltool} can be used
2238 to create it using the @samp{-z} option. In this case @code{dlltool}
2239 will scan the object files specified on its command line looking for
2240 those functions which have been specially marked as being exported and
2241 put entries for them in the .def file it creates.
2243 In order to mark a function as being exported from a DLL, it needs to
2244 have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2245 section of the object file. This can be done in C by using the
2249 asm (".section .drectve");
2250 asm (".ascii \"-export:my_func\"");
2252 int my_func (void) @{ @dots{} @}
2255 The second file needed for DLL creation is an exports file. This file
2256 is linked with the object files that make up the body of the DLL and it
2257 handles the interface between the DLL and the outside world. This is a
2258 binary file and it can be created by giving the @samp{-e} option to
2259 @code{dlltool} when it is creating or reading in a .def file.
2261 The third file needed for DLL creation is the library file that programs
2262 will link with in order to access the functions in the DLL. This file
2263 can be created by giving the @samp{-l} option to dlltool when it
2264 is creating or reading in a .def file.
2266 @code{dlltool} builds the library file by hand, but it builds the
2267 exports file by creating temporary files containing assembler statements
2268 and then assembling these. The @samp{-S} command line option can be
2269 used to specify the path to the assembler that dlltool will use,
2270 and the @samp{-f} option can be used to pass specific flags to that
2271 assembler. The @samp{-n} can be used to prevent dlltool from deleting
2272 these temporary assembler files when it is done, and if @samp{-n} is
2273 specified twice then this will prevent dlltool from deleting the
2274 temporary object files it used to build the library.
2276 Here is an example of creating a DLL from a source file @samp{dll.c} and
2277 also creating a program (from an object file called @samp{program.o})
2282 dlltool -e exports.o -l dll.lib dll.o
2283 gcc dll.o exports.o -o dll.dll
2284 gcc program.o dll.lib -o program
2287 The command line options have the following meanings:
2291 @item -d @var{filename}
2292 @itemx --input-def @var{filename}
2293 @cindex input .def file
2294 Specifies the name of a .def file to be read in and processed.
2296 @item -b @var{filename}
2297 @itemx --base-file @var{filename}
2299 Specifies the name of a base file to be read in and processed. The
2300 contents of this file will be added to the relocation section in the
2301 exports file generated by dlltool.
2303 @item -e @var{filename}
2304 @itemx --output-exp @var{filename}
2305 Specifies the name of the export file to be created by dlltool.
2307 @item -z @var{filename}
2308 @itemx --output-def @var{filename}
2309 Specifies the name of the .def file to be created by dlltool.
2311 @item -l @var{filename}
2312 @itemx --output-lib @var{filename}
2313 Specifies the name of the library file to be created by dlltool.
2315 @item --export-all-symbols
2316 Treat all global and weak defined symbols found in the input object
2317 files as symbols to be exported. There is a small list of symbols which
2318 are not exported by default; see the @code{--no-default-excludes}
2319 option. You may add to the list of symbols to not export by using the
2320 @code{--exclude-symbols} option.
2322 @item --no-export-all-symbols
2323 Only export symbols explicitly listed in an input .def file or in
2324 @samp{.drectve} sections in the input object files. This is the default
2325 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2326 attributes in the source code.
2328 @item --exclude-symbols @var{list}
2329 Do not export the symbols in @var{list}. This is a list of symbol names
2330 separated by comma or colon characters. The symbol names should not
2331 contain a leading underscore. This is only meaningful when
2332 @code{--export-all-symbols} is used.
2334 @item --no-default-excludes
2335 When @code{--export-all-symbols} is used, it will by default avoid
2336 exporting certain special symbols. The current list of symbols to avoid
2337 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2338 @samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2339 to go ahead and export these special symbols. This is only meaningful
2340 when @code{--export-all-symbols} is used.
2343 @itemx --as @var{path}
2344 Specifies the path, including the filename, of the assembler to be used
2345 to create the exports file.
2347 @item -f @var{switches}
2348 @itemx --as-flags @var{switches}
2349 Specifies any specific command line switches to be passed to the
2350 assembler when building the exports file. This option will work even if
2351 the @samp{-S} option is not used. This option only takes one argument,
2352 and if it occurs more than once on the command line, then later
2353 occurrences will override earlier occurrences. So if it is necessary to
2354 pass multiple switches to the assembler they should be enclosed in
2358 @itemx --dll-name @var{name}
2359 Specifies the name to be stored in the .def file as the name of the DLL
2360 when the @samp{-e} option is used. If this option is not present, then
2361 the filename given to the @samp{-e} option will be used as the name of
2364 @item -m @var{machine}
2365 @itemx -machine @var{machine}
2366 Specifies the type of machine for which the library file should be
2367 built. @code{dlltool} has a built in default type, depending upon how
2368 it was created, but this option can be used to override that. This is
2369 normally only useful when creating DLLs for an ARM processor, when the
2370 contents of the DLL are actually encode using THUMB instructions.
2373 @itemx --add-indirect
2374 Specifies that when @code{dlltool} is creating the exports file it
2375 should add a section which allows the exported functions to be
2376 referenced without using the import library. Whatever the hell that
2380 @itemx --add-underscore
2381 Specifies that when @code{dlltool} is creating the exports file it
2382 should prepend an underscore to the names of the exported functions.
2386 Specifies that when @code{dlltool} is creating the exports file it
2387 should not append the string @samp{@@ <number>}. These numbers are
2388 called ordinal numbers and they represent another way of accessing the
2389 function in a DLL, other than by name.
2392 @itemx --add-stdcall-alias
2393 Specifies that when @code{dlltool} is creating the exports file it
2394 should add aliases for stdcall symbols without @samp{@@ <number>}
2395 in addition to the symbols with @samp{@@ <number>}.
2399 Specifies that when @code{dlltool} is creating the exports and library
2400 files it should omit the .idata4 section. This is for compatibility
2401 with certain operating systems.
2405 Specifies that when @code{dlltool} is creating the exports and library
2406 files it should omit the .idata5 section. This is for compatibility
2407 with certain operating systems.
2411 Specifies that @code{dlltool} should mark the objects in the library
2412 file and exports file that it produces as supporting interworking
2413 between ARM and THUMB code.
2417 Makes @code{dlltool} preserve the temporary assembler files it used to
2418 create the exports file. If this option is repeated then dlltool will
2419 also preserve the temporary object files it uses to create the library
2424 Make dlltool describe what it is doing.
2428 Displays a list of command line options and then exits.
2432 Displays dlltool's version number and then exits.
2439 @cindex ELF file information
2443 readelf [ -a | --all ]
2444 [ -h | --file-header]
2445 [ -l | --program-headers | --segments]
2446 [ -S | --section-headers | --sections]
2448 [ -s | --syms | --symbols]
2452 [ -V | --version-info]
2453 [ -D | --use-dynamic]
2454 [ -x <number> | --hex-dump=<number>]
2455 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2459 @var{elffile}@dots{}
2462 @code{readelf} displays information about one or more ELF format object
2463 files. The options control what particular information to display.
2465 @var{elffile}@dots{} are the object files to be examined. At the
2466 moment, @code{readelf} does not support examining archives, nor does it
2467 support examing 64 bit ELF files.
2469 The long and short forms of options, shown here as alternatives, are
2470 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2476 Equivalent to specifiying @samp{--file-header},
2477 @samp{--program-headers}, @samp{--sections}, @samp{--symbols},
2478 @samp{--relocs}, @samp{--dynamic}, @samp{--notes} and
2479 @samp{--version-info}.
2482 @itemx --file-header
2483 @cindex ELF file header information
2484 Displays the information contained in the ELF header at the start of the
2488 @itemx --program-headers
2490 @cindex ELF program header information
2491 @cindex ELF segment information
2492 Displays the information contained in the file's segment headers, if it
2497 @itemx --section-headers
2498 @cindex ELF section information
2499 Displays the information contained in the file's section headers, if it
2505 @cindex ELF symbol table information
2506 Displays the entries in symbol table section of the file, if it has one.
2510 Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2514 @cindex ELF core notes
2515 Displays the contents of the NOTE segment, if it exists.
2519 @cindex ELF reloc information
2520 Displays the contents of the file's relocation section, if it ha one.
2524 @cindex ELF dynamic section information
2525 Displays the contents of the file's dynamic section, if it has one.
2528 @itemx --version-info
2529 @cindex ELF version sections informations
2530 Displays the contents of the version sections in the file, it they
2534 @itemx --use-dynamic
2535 When displaying symbols, this option makes @code{readelf} use the
2536 symbol table in the file's dynamic section, rather than the one in the
2540 @itemx --hex-dump=<number>
2541 Displays the contents of the indicated section as a hexadecimal dump.
2544 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2545 Displays the contents of the debug sections in the file, if any are
2546 present. If one of the optional letters or words follows the switch
2547 then only data found in those specific sections will be dumped.
2550 Display a histogram of bucket list lengths when displaying the contents
2551 of the symbol tables.
2555 Display the version number of readelf.
2559 Display the command line options understood by @code{readelf}.
2564 @node Selecting The Target System
2565 @chapter Selecting the target system
2567 You can specify three aspects of the target system to the @sc{gnu}
2568 binary file utilities, each in several ways:
2578 the linker emulation (which applies to the linker only)
2581 In the following summaries, the lists of ways to specify values are in
2582 order of decreasing precedence. The ways listed first override those
2585 The commands to list valid values only list the values for which the
2586 programs you are running were configured. If they were configured with
2587 @samp{--enable-targets=all}, the commands list most of the available
2588 values, but a few are left out; not all targets can be configured in at
2589 once because some of them can only be configured @dfn{native} (on hosts
2590 with the same type as the target system).
2593 * Target Selection::
2594 * Architecture Selection::
2595 * Linker Emulation Selection::
2598 @node Target Selection
2599 @section Target Selection
2601 A @dfn{target} is an object file format. A given target may be
2602 supported for multiple architectures (@pxref{Architecture Selection}).
2603 A target selection may also have variations for different operating
2604 systems or architectures.
2606 The command to list valid target values is @samp{objdump -i}
2607 (the first column of output contains the relevant information).
2609 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2610 @samp{a.out-sunos-big}.
2612 You can also specify a target using a configuration triplet. This is
2613 the same sort of name that is passed to @file{configure} to specify a
2614 target. When you use a configuration triplet as an argument, it must be
2615 fully canonicalized. You can see the canonical version of a triplet by
2616 running the shell script @file{config.sub} which is included with the
2619 Some sample configuration triplets are: @samp{m68k-hp-bsd},
2620 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2622 @subheading @code{objdump} Target
2628 command line option: @samp{-b} or @samp{--target}
2631 environment variable @code{GNUTARGET}
2634 deduced from the input file
2637 @subheading @code{objcopy} and @code{strip} Input Target
2643 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2646 environment variable @code{GNUTARGET}
2649 deduced from the input file
2652 @subheading @code{objcopy} and @code{strip} Output Target
2658 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2661 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2664 environment variable @code{GNUTARGET}
2667 deduced from the input file
2670 @subheading @code{nm}, @code{size}, and @code{strings} Target
2676 command line option: @samp{--target}
2679 environment variable @code{GNUTARGET}
2682 deduced from the input file
2685 @subheading Linker Input Target
2691 command line option: @samp{-b} or @samp{--format}
2692 (@pxref{Options,,Options,ld.info,Using LD})
2695 script command @code{TARGET}
2696 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2699 environment variable @code{GNUTARGET}
2700 (@pxref{Environment,,Environment,ld.info,Using LD})
2703 the default target of the selected linker emulation
2704 (@pxref{Linker Emulation Selection})
2707 @subheading Linker Output Target
2713 command line option: @samp{-oformat}
2714 (@pxref{Options,,Options,ld.info,Using LD})
2717 script command @code{OUTPUT_FORMAT}
2718 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2721 the linker input target (see ``Linker Input Target'' above)
2724 @node Architecture Selection
2725 @section Architecture selection
2727 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2728 to run. Its name may contain a colon, separating the name of the
2729 processor family from the name of the particular @sc{cpu}.
2731 The command to list valid architecture values is @samp{objdump -i} (the
2732 second column contains the relevant information).
2734 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2736 @subheading @code{objdump} Architecture
2742 command line option: @samp{-m} or @samp{--architecture}
2745 deduced from the input file
2748 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2754 deduced from the input file
2757 @subheading Linker Input Architecture
2763 deduced from the input file
2766 @subheading Linker Output Architecture
2772 script command @code{OUTPUT_ARCH}
2773 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2776 the default architecture from the linker output target
2777 (@pxref{Target Selection})
2780 @node Linker Emulation Selection
2781 @section Linker emulation selection
2783 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2784 the linker default values for the other aspects of the target system.
2785 In particular, it consists of
2795 several ``hook'' functions that are run at certain stages of the linking
2796 process to do special things that some targets require
2799 The command to list valid linker emulation values is @samp{ld -V}.
2801 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2807 command line option: @samp{-m}
2808 (@pxref{Options,,Options,ld.info,Using LD})
2811 environment variable @code{LDEMULATION}
2814 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2815 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2818 @node Reporting Bugs
2819 @chapter Reporting Bugs
2821 @cindex reporting bugs
2823 Your bug reports play an essential role in making the binary utilities
2826 Reporting a bug may help you by bringing a solution to your problem, or
2827 it may not. But in any case the principal function of a bug report is
2828 to help the entire community by making the next version of the binary
2829 utilities work better. Bug reports are your contribution to their
2832 In order for a bug report to serve its purpose, you must include the
2833 information that enables us to fix the bug.
2836 * Bug Criteria:: Have you found a bug?
2837 * Bug Reporting:: How to report bugs
2841 @section Have you found a bug?
2842 @cindex bug criteria
2844 If you are not sure whether you have found a bug, here are some guidelines:
2847 @cindex fatal signal
2850 If a binary utility gets a fatal signal, for any input whatever, that is
2851 a bug. Reliable utilities never crash.
2853 @cindex error on valid input
2855 If a binary utility produces an error message for valid input, that is a
2859 If you are an experienced user of binary utilities, your suggestions for
2860 improvement are welcome in any case.
2864 @section How to report bugs
2866 @cindex bugs, reporting
2868 A number of companies and individuals offer support for @sc{gnu}
2869 products. If you obtained the binary utilities from a support
2870 organization, we recommend you contact that organization first.
2872 You can find contact information for many support companies and
2873 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2876 In any event, we also recommend that you send bug reports for the binary
2877 utilities to @samp{bug-gnu-utils@@gnu.org}.
2879 The fundamental principle of reporting bugs usefully is this:
2880 @strong{report all the facts}. If you are not sure whether to state a
2881 fact or leave it out, state it!
2883 Often people omit facts because they think they know what causes the
2884 problem and assume that some details do not matter. Thus, you might
2885 assume that the name of a file you use in an example does not matter.
2886 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2887 a stray memory reference which happens to fetch from the location where
2888 that pathname is stored in memory; perhaps, if the pathname were
2889 different, the contents of that location would fool the utility into
2890 doing the right thing despite the bug. Play it safe and give a
2891 specific, complete example. That is the easiest thing for you to do,
2892 and the most helpful.
2894 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2895 it is new to us. Therefore, always write your bug reports on the assumption
2896 that the bug has not been reported previously.
2898 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2899 bell?'' Those bug reports are useless, and we urge everyone to
2900 @emph{refuse to respond to them} except to chide the sender to report
2903 To enable us to fix the bug, you should include all these things:
2907 The version of the utility. Each utility announces it if you start it
2908 with the @samp{--version} argument.
2910 Without this, we will not know whether there is any point in looking for
2911 the bug in the current version of the binary utilities.
2914 Any patches you may have applied to the source, including any patches
2915 made to the @code{BFD} library.
2918 The type of machine you are using, and the operating system name and
2922 What compiler (and its version) was used to compile the utilities---e.g.
2926 The command arguments you gave the utility to observe the bug. To
2927 guarantee you will not omit something important, list them all. A copy
2928 of the Makefile (or the output from make) is sufficient.
2930 If we were to try to guess the arguments, we would probably guess wrong
2931 and then we might not encounter the bug.
2934 A complete input file, or set of input files, that will reproduce the
2935 bug. If the utility is reading an object file or files, then it is
2936 generally most helpful to send the actual object files, uuencoded if
2937 necessary to get them through the mail system. Note that
2938 @samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2939 sending very large files to it. Making the files available for
2940 anonymous FTP is OK.
2942 If the source files were produced exclusively using @sc{gnu} programs
2943 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2944 may be OK to send the source files rather than the object files. In
2945 this case, be sure to say exactly what version of @code{gcc}, or
2946 whatever, was used to produce the object files. Also say how
2947 @code{gcc}, or whatever, was configured.
2950 A description of what behavior you observe that you believe is
2951 incorrect. For example, ``It gets a fatal signal.''
2953 Of course, if the bug is that the utility gets a fatal signal, then we
2954 will certainly notice it. But if the bug is incorrect output, we might
2955 not notice unless it is glaringly wrong. You might as well not give us
2956 a chance to make a mistake.
2958 Even if the problem you experience is a fatal signal, you should still
2959 say so explicitly. Suppose something strange is going on, such as your
2960 copy of the utility is out of synch, or you have encountered a bug in
2961 the C library on your system. (This has happened!) Your copy might
2962 crash and ours would not. If you told us to expect a crash, then when
2963 ours fails to crash, we would know that the bug was not happening for
2964 us. If you had not told us to expect a crash, then we would not be able
2965 to draw any conclusion from our observations.
2968 If you wish to suggest changes to the source, send us context diffs, as
2969 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2970 option. Always send diffs from the old file to the new file. If you
2971 wish to discuss something in the @code{ld} source, refer to it by
2972 context, not by line number.
2974 The line numbers in our development sources will not match those in your
2975 sources. Your line numbers would convey no useful information to us.
2978 Here are some things that are not necessary:
2982 A description of the envelope of the bug.
2984 Often people who encounter a bug spend a lot of time investigating
2985 which changes to the input file will make the bug go away and which
2986 changes will not affect it.
2988 This is often time consuming and not very useful, because the way we
2989 will find the bug is by running a single example under the debugger
2990 with breakpoints, not by pure deduction from a series of examples.
2991 We recommend that you save your time for something else.
2993 Of course, if you can find a simpler example to report @emph{instead}
2994 of the original one, that is a convenience for us. Errors in the
2995 output will be easier to spot, running under the debugger will take
2996 less time, and so on.
2998 However, simplification is not vital; if you do not want to do this,
2999 report the bug anyway and send us the entire test case you used.
3002 A patch for the bug.
3004 A patch for the bug does help us if it is a good one. But do not omit
3005 the necessary information, such as the test case, on the assumption that
3006 a patch is all we need. We might see problems with your patch and decide
3007 to fix the problem another way, or we might not understand it at all.
3009 Sometimes with programs as complicated as the binary utilities it is
3010 very hard to construct an example that will make the program follow a
3011 certain path through the code. If you do not send us the example, we
3012 will not be able to construct one, so we will not be able to verify that
3015 And if we cannot understand what bug you are trying to fix, or why your
3016 patch should be an improvement, we will not install it. A test case will
3017 help us to understand.
3020 A guess about what the bug is or what it depends on.
3022 Such guesses are usually wrong. Even we cannot guess right about such
3023 things without first using the debugger to find the facts.