1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
10 * Binutils: (binutils). The GNU binary utilities.
11 * ar: (binutils)ar. Create, modify, and extract from archives
12 * nm: (binutils)nm. List symbols from object files
13 * objcopy: (binutils)objcopy. Copy and translate object files
14 * objdump: (binutils)objdump. Display information from object files
15 * ranlib: (binutils)ranlib. Generate index to archive contents
16 * readelf: (binutils)readelf. Display the contents of ELF format files.
17 * size: (binutils)size. List section sizes and total size
18 * strings: (binutils)strings. List printable strings from files
19 * strip: (binutils)strip. Discard symbols
20 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
21 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
22 * addr2line: (binutils)addr2line. Convert addresses to file and line
23 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
24 * windres: (binutils)windres. Manipulate Windows resources
25 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
31 @c man begin COPYRIGHT
32 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
33 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
35 Permission is granted to copy, distribute and/or modify this document
36 under the terms of the GNU Free Documentation License, Version 1.1
37 or any later version published by the Free Software Foundation;
38 with no Invariant Sections, with no Front-Cover Texts, and with no
39 Back-Cover Texts. A copy of the license is included in the
40 section entitled ``GNU Free Documentation License''.
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries a copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
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, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
58 @c 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
60 @c This text may be freely distributed under the terms of the GNU
61 @c Free Documentation License.
64 @setchapternewpage odd
65 @settitle @sc{gnu} Binary Utilities
68 @title The @sc{gnu} Binary Utilities
69 @subtitle Version @value{VERSION}
71 @subtitle @value{UPDATED}
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
84 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
99 This brief manual contains documentation for the @sc{gnu} binary
100 utilities (collectively version @value{VERSION}):
105 Create, modify, and extract from archives
108 List symbols from object files
111 Copy and translate object files
114 Display information from object files
117 Generate index to archive contents
120 Display the contents of ELF format files.
123 List file section sizes and total size
126 List printable strings from files
132 Demangle encoded C++ symbols (on MS-DOS, this program is named
136 Convert addresses into file names and line numbers
139 Convert object code into a Netware Loadable Module
142 Manipulate Windows resources
145 Create the files needed to build and use Dynamic Link Libraries
149 This document is distributed under the terms of the GNU Free
150 Documentation License. A copy of the license is included in the
151 section entitled "GNU Free Documentation License".
154 * ar:: Create, modify, and extract from archives
155 * nm:: List symbols from object files
156 * objcopy:: Copy and translate object files
157 * objdump:: Display information from object files
158 * ranlib:: Generate index to archive contents
159 * readelf:: Display the contents of ELF format files.
160 * size:: List section sizes and total size
161 * strings:: List printable strings from files
162 * strip:: Discard symbols
163 * c++filt:: Filter to demangle encoded C++ symbols
164 * cxxfilt: c++filt. MS-DOS name for c++filt
165 * addr2line:: Convert addresses to file and line
166 * nlmconv:: Converts object code into an NLM
167 * windres:: Manipulate Windows resources
168 * dlltool:: Create files needed to build and use DLLs
169 * Selecting The Target System:: How these utilities determine the target.
170 * Reporting Bugs:: Reporting Bugs
171 * GNU Free Documentation License:: GNU Free Documentation License
180 @cindex collections of files
182 @c man title ar create, modify, and extract from archives
185 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
186 ar -M [ <mri-script ]
189 @c man begin DESCRIPTION ar
191 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
192 archives. An @dfn{archive} is a single file holding a collection of
193 other files in a structure that makes it possible to retrieve
194 the original individual files (called @dfn{members} of the archive).
196 The original files' contents, mode (permissions), timestamp, owner, and
197 group are preserved in the archive, and can be restored on
201 @sc{gnu} @command{ar} can maintain archives whose members have names of any
202 length; however, depending on how @command{ar} is configured on your
203 system, a limit on member-name length may be imposed for compatibility
204 with archive formats maintained with other tools. If it exists, the
205 limit is often 15 characters (typical of formats related to a.out) or 16
206 characters (typical of formats related to coff).
209 @command{ar} is considered a binary utility because archives of this sort
210 are most often used as @dfn{libraries} holding commonly needed
214 @command{ar} creates an index to the symbols defined in relocatable
215 object modules in the archive when you specify the modifier @samp{s}.
216 Once created, this index is updated in the archive whenever @command{ar}
217 makes a change to its contents (save for the @samp{q} update operation).
218 An archive with such an index speeds up linking to the library, and
219 allows routines in the library to call each other without regard to
220 their placement in the archive.
222 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
223 table. If an archive lacks the table, another form of @command{ar} called
224 @command{ranlib} can be used to add just the table.
226 @cindex compatibility, @command{ar}
227 @cindex @command{ar} compatibility
228 @sc{gnu} @command{ar} is designed to be compatible with two different
229 facilities. You can control its activity using command-line options,
230 like the different varieties of @command{ar} on Unix systems; or, if you
231 specify the single command-line option @option{-M}, you can control it
232 with a script supplied via standard input, like the MRI ``librarian''
238 * ar cmdline:: Controlling @command{ar} on the command line
239 * ar scripts:: Controlling @command{ar} with a script
244 @section Controlling @command{ar} on the Command Line
247 @c man begin SYNOPSIS ar
248 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
252 @cindex Unix compatibility, @command{ar}
253 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
254 arguments to execute: one keyletter specifying the @emph{operation}
255 (optionally accompanied by other keyletters specifying
256 @emph{modifiers}), and the archive name to act on.
258 Most operations can also accept further @var{member} arguments,
259 specifying particular files to operate on.
261 @c man begin OPTIONS ar
263 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
264 flags @var{mod} in any order, within the first command-line argument.
266 If you wish, you may begin the first command-line argument with a
269 @cindex operations on archive
270 The @var{p} keyletter specifies what operation to execute; it may be
271 any of the following, but you must specify only one of them:
275 @cindex deleting from archive
276 @emph{Delete} modules from the archive. Specify the names of modules to
277 be deleted as @var{member}@dots{}; the archive is untouched if you
278 specify no files to delete.
280 If you specify the @samp{v} modifier, @command{ar} lists each module
284 @cindex moving in archive
285 Use this operation to @emph{move} members in an archive.
287 The ordering of members in an archive can make a difference in how
288 programs are linked using the library, if a symbol is defined in more
291 If no modifiers are used with @code{m}, any members you name in the
292 @var{member} arguments are moved to the @emph{end} of the archive;
293 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
294 specified place instead.
297 @cindex printing from archive
298 @emph{Print} the specified members of the archive, to the standard
299 output file. If the @samp{v} modifier is specified, show the member
300 name before copying its contents to standard output.
302 If you specify no @var{member} arguments, all the files in the archive are
306 @cindex quick append to archive
307 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
308 @var{archive}, without checking for replacement.
310 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
311 operation; new members are always placed at the end of the archive.
313 The modifier @samp{v} makes @command{ar} list each file as it is appended.
315 Since the point of this operation is speed, the archive's symbol table
316 index is not updated, even if it already existed; you can use @samp{ar s} or
317 @command{ranlib} explicitly to update the symbol table index.
319 However, too many different systems assume quick append rebuilds the
320 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
323 @cindex replacement in archive
324 Insert the files @var{member}@dots{} into @var{archive} (with
325 @emph{replacement}). This operation differs from @samp{q} in that any
326 previously existing members are deleted if their names match those being
329 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
330 displays an error message, and leaves undisturbed any existing members
331 of the archive matching that name.
333 By default, new members are added at the end of the file; but you may
334 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
335 placement relative to some existing member.
337 The modifier @samp{v} used with this operation elicits a line of
338 output for each file inserted, along with one of the letters @samp{a} or
339 @samp{r} to indicate whether the file was appended (no old member
340 deleted) or replaced.
343 @cindex contents of archive
344 Display a @emph{table} listing the contents of @var{archive}, or those
345 of the files listed in @var{member}@dots{} that are present in the
346 archive. Normally only the member name is shown; if you also want to
347 see the modes (permissions), timestamp, owner, group, and size, you can
348 request that by also specifying the @samp{v} modifier.
350 If you do not specify a @var{member}, all files in the archive
353 @cindex repeated names in archive
354 @cindex name duplication in archive
355 If there is more than one file with the same name (say, @samp{fie}) in
356 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
357 first instance; to see them all, you must ask for a complete
358 listing---in our example, @samp{ar t b.a}.
359 @c WRS only; per Gumby, this is implementation-dependent, and in a more
360 @c recent case in fact works the other way.
363 @cindex extract from archive
364 @emph{Extract} members (named @var{member}) from the archive. You can
365 use the @samp{v} modifier with this operation, to request that
366 @command{ar} list each name as it extracts it.
368 If you do not specify a @var{member}, all files in the archive
373 A number of modifiers (@var{mod}) may immediately follow the @var{p}
374 keyletter, to specify variations on an operation's behavior:
378 @cindex relative placement in archive
379 Add new files @emph{after} an existing member of the
380 archive. If you use the modifier @samp{a}, the name of an existing archive
381 member must be present as the @var{relpos} argument, before the
382 @var{archive} specification.
385 Add new files @emph{before} an existing member of the
386 archive. If you use the modifier @samp{b}, the name of an existing archive
387 member must be present as the @var{relpos} argument, before the
388 @var{archive} specification. (same as @samp{i}).
391 @cindex creating archives
392 @emph{Create} the archive. The specified @var{archive} is always
393 created if it did not exist, when you request an update. But a warning is
394 issued unless you specify in advance that you expect to create it, by
398 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
399 names of any length. This will cause it to create archives which are
400 not compatible with the native @command{ar} program on some systems. If
401 this is a concern, the @samp{f} modifier may be used to truncate file
402 names when putting them in the archive.
405 Insert new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{i}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{b}).
411 This modifier is accepted but not used.
412 @c whaffor ar l modifier??? presumably compat; with
413 @c what???---doc@@cygnus.com, 25jan91
416 Uses the @var{count} parameter. This is used if there are multiple
417 entries in the archive with the same name. Extract or delete instance
418 @var{count} of the given name from the archive.
421 @cindex dates in archive
422 Preserve the @emph{original} dates of members when extracting them. If
423 you do not specify this modifier, files extracted from the archive
424 are stamped with the time of extraction.
427 Use the full path name when matching names in the archive. @sc{gnu}
428 @command{ar} can not create an archive with a full path name (such archives
429 are not POSIX complaint), but other archive creators can. This option
430 will cause @sc{gnu} @command{ar} to match file names using a complete path
431 name, which can be convenient when extracting a single file from an
432 archive created by another tool.
435 @cindex writing archive index
436 Write an object-file index into the archive, or update an existing one,
437 even if no other change is made to the archive. You may use this modifier
438 flag either with any operation, or alone. Running @samp{ar s} on an
439 archive is equivalent to running @samp{ranlib} on it.
442 @cindex not writing archive index
443 Do not generate an archive symbol table. This can speed up building a
444 large library in several steps. The resulting archive can not be used
445 with the linker. In order to build a symbol table, you must omit the
446 @samp{S} modifier on the last execution of @samp{ar}, or you must run
447 @samp{ranlib} on the archive.
450 @cindex updating an archive
451 Normally, @samp{ar r}@dots{} inserts all files
452 listed into the archive. If you would like to insert @emph{only} those
453 of the files you list that are newer than existing members of the same
454 names, use this modifier. The @samp{u} modifier is allowed only for the
455 operation @samp{r} (replace). In particular, the combination @samp{qu} is
456 not allowed, since checking the timestamps would lose any speed
457 advantage from the operation @samp{q}.
460 This modifier requests the @emph{verbose} version of an operation. Many
461 operations display additional information, such as filenames processed,
462 when the modifier @samp{v} is appended.
465 This modifier shows the version number of @command{ar}.
468 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
469 compatibility with AIX. The behaviour produced by this option is the
470 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
471 @samp{-X} options; in particular, it does not support @option{-X32}
472 which is the default for AIX @command{ar}.
477 @c man begin SEEALSO ar
478 nm(1), ranlib(1), and the Info entries for @file{binutils}.
483 @section Controlling @command{ar} with a Script
486 ar -M [ <@var{script} ]
489 @cindex MRI compatibility, @command{ar}
490 @cindex scripts, @command{ar}
491 If you use the single command-line option @samp{-M} with @command{ar}, you
492 can control its operation with a rudimentary command language. This
493 form of @command{ar} operates interactively if standard input is coming
494 directly from a terminal. During interactive use, @command{ar} prompts for
495 input (the prompt is @samp{AR >}), and continues executing even after
496 errors. If you redirect standard input to a script file, no prompts are
497 issued, and @command{ar} abandons execution (with a nonzero exit code)
500 The @command{ar} command language is @emph{not} designed to be equivalent
501 to the command-line options; in fact, it provides somewhat less control
502 over archives. The only purpose of the command language is to ease the
503 transition to @sc{gnu} @command{ar} for developers who already have scripts
504 written for the MRI ``librarian'' program.
506 The syntax for the @command{ar} command language is straightforward:
509 commands are recognized in upper or lower case; for example, @code{LIST}
510 is the same as @code{list}. In the following descriptions, commands are
511 shown in upper case for clarity.
514 a single command may appear on each line; it is the first word on the
518 empty lines are allowed, and have no effect.
521 comments are allowed; text after either of the characters @samp{*}
522 or @samp{;} is ignored.
525 Whenever you use a list of names as part of the argument to an @command{ar}
526 command, you can separate the individual names with either commas or
527 blanks. Commas are shown in the explanations below, for clarity.
530 @samp{+} is used as a line continuation character; if @samp{+} appears
531 at the end of a line, the text on the following line is considered part
532 of the current command.
535 Here are the commands you can use in @command{ar} scripts, or when using
536 @command{ar} interactively. Three of them have special significance:
538 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
539 a temporary file required for most of the other commands.
541 @code{SAVE} commits the changes so far specified by the script. Prior
542 to @code{SAVE}, commands affect only the temporary copy of the current
546 @item ADDLIB @var{archive}
547 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
548 Add all the contents of @var{archive} (or, if specified, each named
549 @var{module} from @var{archive}) to the current archive.
551 Requires prior use of @code{OPEN} or @code{CREATE}.
553 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
554 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
555 @c else like "ar q..."
556 Add each named @var{member} as a module in the current archive.
558 Requires prior use of @code{OPEN} or @code{CREATE}.
561 Discard the contents of the current archive, canceling the effect of
562 any operations since the last @code{SAVE}. May be executed (with no
563 effect) even if no current archive is specified.
565 @item CREATE @var{archive}
566 Creates an archive, and makes it the current archive (required for many
567 other commands). The new archive is created with a temporary name; it
568 is not actually saved as @var{archive} until you use @code{SAVE}.
569 You can overwrite existing archives; similarly, the contents of any
570 existing file named @var{archive} will not be destroyed until @code{SAVE}.
572 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
573 Delete each listed @var{module} from the current archive; equivalent to
574 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
576 Requires prior use of @code{OPEN} or @code{CREATE}.
578 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
579 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
580 List each named @var{module} present in @var{archive}. The separate
581 command @code{VERBOSE} specifies the form of the output: when verbose
582 output is off, output is like that of @samp{ar -t @var{archive}
583 @var{module}@dots{}}. When verbose output is on, the listing is like
584 @samp{ar -tv @var{archive} @var{module}@dots{}}.
586 Output normally goes to the standard output stream; however, if you
587 specify @var{outputfile} as a final argument, @command{ar} directs the
591 Exit from @command{ar}, with a @code{0} exit code to indicate successful
592 completion. This command does not save the output file; if you have
593 changed the current archive since the last @code{SAVE} command, those
596 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
597 Extract each named @var{module} from the current archive, writing them
598 into the current directory as separate files. Equivalent to @samp{ar -x
599 @var{archive} @var{module}@dots{}}.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 @c FIXME Tokens but no commands???
611 Display full contents of the current archive, in ``verbose'' style
612 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
613 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
614 enhancement, rather than present for MRI compatibility.)
616 Requires prior use of @code{OPEN} or @code{CREATE}.
618 @item OPEN @var{archive}
619 Opens an existing archive for use as the current archive (required for
620 many other commands). Any changes as the result of subsequent commands
621 will not actually affect @var{archive} until you next use @code{SAVE}.
623 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
624 In the current archive, replace each existing @var{module} (named in
625 the @code{REPLACE} arguments) from files in the current working directory.
626 To execute this command without errors, both the file, and the module in
627 the current archive, must exist.
629 Requires prior use of @code{OPEN} or @code{CREATE}.
632 Toggle an internal flag governing the output from @code{DIRECTORY}.
633 When the flag is on, @code{DIRECTORY} output matches output from
634 @samp{ar -tv }@dots{}.
637 Commit your changes to the current archive, and actually save it as a
638 file with the name specified in the last @code{CREATE} or @code{OPEN}
641 Requires prior use of @code{OPEN} or @code{CREATE}.
650 The @sc{gnu} linker @command{ld} is now described in a separate manual.
651 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
659 @c man title nm list symbols from object files
662 @c man begin SYNOPSIS nm
663 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
664 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
665 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
666 [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}]
667 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
668 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
669 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
670 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
671 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
672 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
676 @c man begin DESCRIPTION nm
677 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
678 If no object files are listed as arguments, @command{nm} assumes the file
681 For each symbol, @command{nm} shows:
685 The symbol value, in the radix selected by options (see below), or
686 hexadecimal by default.
689 The symbol type. At least the following types are used; others are, as
690 well, depending on the object file format. If lowercase, the symbol is
691 local; if uppercase, the symbol is global (external).
693 @c Some more detail on exactly what these symbol types are used for
697 The symbol's value is absolute, and will not be changed by further
701 The symbol is in the uninitialized data section (known as BSS).
704 The symbol is common. Common symbols are uninitialized data. When
705 linking, multiple common symbols may appear with the same name. If the
706 symbol is defined anywhere, the common symbols are treated as undefined
709 For more details on common symbols, see the discussion of
710 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
714 The symbol is in the initialized data section.
717 The symbol is in an initialized data section for small objects. Some
718 object file formats permit more efficient access to small data objects,
719 such as a global int variable as opposed to a large global array.
722 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
723 extension to the a.out object file format which is rarely used.
726 The symbol is a debugging symbol.
729 The symbol is in a read only data section.
732 The symbol is in an uninitialized data section for small objects.
735 The symbol is in the text (code) section.
738 The symbol is undefined.
741 The symbol is a weak object. When a weak defined symbol is linked with
742 a normal defined symbol, the normal defined symbol is used with no error.
743 When a weak undefined symbol is linked and the symbol is not defined,
744 the value of the weak symbol becomes zero with no error.
747 The symbol is a weak symbol that has not been specifically tagged as a
748 weak object symbol. When a weak defined symbol is linked with a normal
749 defined symbol, the normal defined symbol is used with no error.
750 When a weak undefined symbol is linked and the symbol is not defined,
751 the value of the symbol is determined in a system-specific manner without
752 error. On some systems, uppercase indicates that a default value has been
757 The symbol is a stabs symbol in an a.out object file. In this case, the
758 next values printed are the stabs other field, the stabs desc field, and
759 the stab type. Stabs symbols are used to hold debugging information.
761 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
762 ``stabs'' debug format}.
766 The symbol type is unknown, or object file format specific.
775 @c man begin OPTIONS nm
776 The long and short forms of options, shown here as alternatives, are
782 @itemx --print-file-name
783 @cindex input file name
785 @cindex source file name
786 Precede each symbol by the name of the input file (or archive member)
787 in which it was found, rather than identifying the input file once only,
788 before all of its symbols.
792 @cindex debugging symbols
793 Display all symbols, even debugger-only symbols; normally these are not
797 @cindex @command{nm} format
798 @cindex @command{nm} compatibility
799 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
802 @itemx --demangle[=@var{style}]
803 @cindex demangling in nm
804 Decode (@dfn{demangle}) low-level symbol names into user-level names.
805 Besides removing any initial underscore prepended by the system, this
806 makes C++ function names readable. Different compilers have different
807 mangling styles. The optional demangling style argument can be used to
808 choose an appropriate demangling style for your compiler. @xref{c++filt},
809 for more information on demangling.
812 Do not demangle low-level symbol names. This is the default.
816 @cindex dynamic symbols
817 Display the dynamic symbols rather than the normal symbols. This is
818 only meaningful for dynamic objects, such as certain types of shared
821 @item -f @var{format}
822 @itemx --format=@var{format}
823 @cindex @command{nm} format
824 @cindex @command{nm} compatibility
825 Use the output format @var{format}, which can be @code{bsd},
826 @code{sysv}, or @code{posix}. The default is @code{bsd}.
827 Only the first character of @var{format} is significant; it can be
828 either upper or lower case.
832 @cindex external symbols
833 Display only external symbols.
836 @itemx --line-numbers
837 @cindex symbol line numbers
838 For each symbol, use debugging information to try to find a filename and
839 line number. For a defined symbol, look for the line number of the
840 address of the symbol. For an undefined symbol, look for the line
841 number of a relocation entry which refers to the symbol. If line number
842 information can be found, print it after the other symbol information.
846 @itemx --numeric-sort
847 Sort symbols numerically by their addresses, rather than alphabetically
852 @cindex sorting symbols
853 Do not bother to sort the symbols in any order; print them in the order
858 Use the POSIX.2 standard output format instead of the default format.
859 Equivalent to @samp{-f posix}.
863 Print size, not the value, of defined symbols for the @code{bsd} output format.
867 @cindex symbol index, listing
868 When listing symbols from archive members, include the index: a mapping
869 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
870 contain definitions for which names.
873 @itemx --reverse-sort
874 Reverse the order of the sort (whether numeric or alphabetic); let the
878 Sort symbols by size. The size is computed as the difference between
879 the value of the symbol and the value of the symbol with the next higher
880 value. If the @code{bsd} output format is used the size of the symbol
881 is printed, rather than the value, and @samp{-S} must be used in order
882 both size and value to be printed.
885 Display symbols which have a target-specific special meaning. These
886 symbols are usually used by the target for some special processing and
887 are not normally helpful when included included in the normal symbol
888 lists. For example for ARM targets this option would skip the mapping
889 symbols used to mark transistions between ARM code, THUMB code and
893 @itemx --radix=@var{radix}
894 Use @var{radix} as the radix for printing the symbol values. It must be
895 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
897 @item --target=@var{bfdname}
898 @cindex object code format
899 Specify an object code format other than your system's default format.
900 @xref{Target Selection}, for more information.
903 @itemx --undefined-only
904 @cindex external symbols
905 @cindex undefined symbols
906 Display only undefined symbols (those external to each object file).
909 @cindex external symbols
910 @cindex undefined symbols
911 Display only defined symbols for each object file.
915 Show the version number of @command{nm} and exit.
918 This option is ignored for compatibility with the AIX version of
919 @command{nm}. It takes one parameter which must be the string
920 @option{32_64}. The default mode of AIX @command{nm} corresponds
921 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
924 Show a summary of the options to @command{nm} and exit.
930 @c man begin SEEALSO nm
931 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
938 @c man title objcopy copy and translate object files
941 @c man begin SYNOPSIS objcopy
942 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
943 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
944 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
945 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
946 [@option{-S}|@option{--strip-all}]
947 [@option{-g}|@option{--strip-debug}]
948 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
949 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
950 [@option{--strip-unneeded-symbol=}@var{symbolname}]
951 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
952 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
953 [@option{--globalize-symbol=}@var{symbolname}]
954 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
955 [@option{-w}|@option{--wildcard}]
956 [@option{-x}|@option{--discard-all}]
957 [@option{-X}|@option{--discard-locals}]
958 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
959 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
960 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
961 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
962 [@option{-p}|@option{--preserve-dates}]
963 [@option{--debugging}]
964 [@option{--gap-fill=}@var{val}]
965 [@option{--pad-to=}@var{address}]
966 [@option{--set-start=}@var{val}]
967 [@option{--adjust-start=}@var{incr}]
968 [@option{--change-addresses=}@var{incr}]
969 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
970 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
971 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
972 [@option{--change-warnings}] [@option{--no-change-warnings}]
973 [@option{--set-section-flags} @var{section}=@var{flags}]
974 [@option{--add-section} @var{sectionname}=@var{filename}]
975 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
976 [@option{--change-leading-char}] [@option{--remove-leading-char}]
977 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
978 [@option{--redefine-sym} @var{old}=@var{new}]
979 [@option{--redefine-syms=}@var{filename}]
981 [@option{--keep-symbols=}@var{filename}]
982 [@option{--strip-symbols=}@var{filename}]
983 [@option{--strip-unneeded-symbols=}@var{filename}]
984 [@option{--keep-global-symbols=}@var{filename}]
985 [@option{--localize-symbols=}@var{filename}]
986 [@option{--globalize-symbols=}@var{filename}]
987 [@option{--weaken-symbols=}@var{filename}]
988 [@option{--alt-machine-code=}@var{index}]
989 [@option{--prefix-symbols=}@var{string}]
990 [@option{--prefix-sections=}@var{string}]
991 [@option{--prefix-alloc-sections=}@var{string}]
992 [@option{--add-gnu-debuglink=}@var{path-to-file}]
993 [@option{--only-keep-debug}]
994 [@option{--writable-text}]
995 [@option{--readonly-text}]
998 [@option{-v}|@option{--verbose}]
999 [@option{-V}|@option{--version}]
1000 [@option{--help}] [@option{--info}]
1001 @var{infile} [@var{outfile}]
1005 @c man begin DESCRIPTION objcopy
1006 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1007 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1008 read and write the object files. It can write the destination object
1009 file in a format different from that of the source object file. The
1010 exact behavior of @command{objcopy} is controlled by command-line options.
1011 Note that @command{objcopy} should be able to copy a fully linked file
1012 between any two formats. However, copying a relocatable object file
1013 between any two formats may not work as expected.
1015 @command{objcopy} creates temporary files to do its translations and
1016 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1017 translation work; it has access to all the formats described in @sc{bfd}
1018 and thus is able to recognize most formats without being told
1019 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1021 @command{objcopy} can be used to generate S-records by using an output
1022 target of @samp{srec} (e.g., use @samp{-O srec}).
1024 @command{objcopy} can be used to generate a raw binary file by using an
1025 output target of @samp{binary} (e.g., use @option{-O binary}). When
1026 @command{objcopy} generates a raw binary file, it will essentially produce
1027 a memory dump of the contents of the input object file. All symbols and
1028 relocation information will be discarded. The memory dump will start at
1029 the load address of the lowest section copied into the output file.
1031 When generating an S-record or a raw binary file, it may be helpful to
1032 use @option{-S} to remove sections containing debugging information. In
1033 some cases @option{-R} will be useful to remove sections which contain
1034 information that is not needed by the binary file.
1036 Note---@command{objcopy} is not able to change the endianness of its input
1037 files. If the input format has an endianness (some formats do not),
1038 @command{objcopy} can only copy the inputs into file formats that have the
1039 same endianness or which have no endianness (e.g., @samp{srec}).
1043 @c man begin OPTIONS objcopy
1047 @itemx @var{outfile}
1048 The input and output files, respectively.
1049 If you do not specify @var{outfile}, @command{objcopy} creates a
1050 temporary file and destructively renames the result with
1051 the name of @var{infile}.
1053 @item -I @var{bfdname}
1054 @itemx --input-target=@var{bfdname}
1055 Consider the source file's object format to be @var{bfdname}, rather than
1056 attempting to deduce it. @xref{Target Selection}, for more information.
1058 @item -O @var{bfdname}
1059 @itemx --output-target=@var{bfdname}
1060 Write the output file using the object format @var{bfdname}.
1061 @xref{Target Selection}, for more information.
1063 @item -F @var{bfdname}
1064 @itemx --target=@var{bfdname}
1065 Use @var{bfdname} as the object format for both the input and the output
1066 file; i.e., simply transfer data from source to destination with no
1067 translation. @xref{Target Selection}, for more information.
1069 @item -B @var{bfdarch}
1070 @itemx --binary-architecture=@var{bfdarch}
1071 Useful when transforming a raw binary input file into an object file.
1072 In this case the output architecture can be set to @var{bfdarch}. This
1073 option will be ignored if the input file has a known @var{bfdarch}. You
1074 can access this binary data inside a program by referencing the special
1075 symbols that are created by the conversion process. These symbols are
1076 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1077 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1078 an object file and then access it in your code using these symbols.
1080 @item -j @var{sectionname}
1081 @itemx --only-section=@var{sectionname}
1082 Copy only the named section from the input file to the output file.
1083 This option may be given more than once. Note that using this option
1084 inappropriately may make the output file unusable.
1086 @item -R @var{sectionname}
1087 @itemx --remove-section=@var{sectionname}
1088 Remove any section named @var{sectionname} from the output file. This
1089 option may be given more than once. Note that using this option
1090 inappropriately may make the output file unusable.
1094 Do not copy relocation and symbol information from the source file.
1097 @itemx --strip-debug
1098 Do not copy debugging symbols or sections from the source file.
1100 @item --strip-unneeded
1101 Strip all symbols that are not needed for relocation processing.
1103 @item -K @var{symbolname}
1104 @itemx --keep-symbol=@var{symbolname}
1105 When stripping symbols, keep symbol @var{symbolname} even if it would
1106 normally be stripped. This option may be given more than once.
1108 @item -N @var{symbolname}
1109 @itemx --strip-symbol=@var{symbolname}
1110 Do not copy symbol @var{symbolname} from the source file. This option
1111 may be given more than once.
1113 @item --strip-unneeded-symbol=@var{symbolname}
1114 Do not copy symbol @var{symbolname} from the source file unless it is needed
1115 by a relocation. This option may be given more than once.
1117 @item -G @var{symbolname}
1118 @itemx --keep-global-symbol=@var{symbolname}
1119 Keep only symbol @var{symbolname} global. Make all other symbols local
1120 to the file, so that they are not visible externally. This option may
1121 be given more than once.
1123 @item -L @var{symbolname}
1124 @itemx --localize-symbol=@var{symbolname}
1125 Make symbol @var{symbolname} local to the file, so that it is not
1126 visible externally. This option may be given more than once.
1128 @item -W @var{symbolname}
1129 @itemx --weaken-symbol=@var{symbolname}
1130 Make symbol @var{symbolname} weak. This option may be given more than once.
1132 @item --globalize-symbol=@var{symbolname}
1133 Give symbol @var{symbolname} global scoping so that it is visible
1134 outside of the file in which it is defined. This option may be given
1139 Permit regular expressions in @var{symbolname}s used in other command
1140 line options. The question mark (?), asterisk (*), backslash (\) and
1141 square brackets ([]) operators can be used anywhere in the symbol
1142 name. If the first character of the symbol name is the exclamation
1143 point (!) then the sense of the switch is reversed for that symbol.
1150 would cause objcopy to weaken all symbols that start with ``fo''
1151 except for the symbol ``foo''.
1154 @itemx --discard-all
1155 Do not copy non-global symbols from the source file.
1156 @c FIXME any reason to prefer "non-global" to "local" here?
1159 @itemx --discard-locals
1160 Do not copy compiler-generated local symbols.
1161 (These usually start with @samp{L} or @samp{.}.)
1164 @itemx --byte=@var{byte}
1165 Keep only every @var{byte}th byte of the input file (header data is not
1166 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1167 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1168 option, or the default of 4. This option is useful for creating files
1169 to program @sc{rom}. It is typically used with an @code{srec} output
1172 @item -i @var{interleave}
1173 @itemx --interleave=@var{interleave}
1174 Only copy one out of every @var{interleave} bytes. Select which byte to
1175 copy with the @option{-b} or @option{--byte} option. The default is 4.
1176 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1180 @itemx --preserve-dates
1181 Set the access and modification dates of the output file to be the same
1182 as those of the input file.
1185 Convert debugging information, if possible. This is not the default
1186 because only certain debugging formats are supported, and the
1187 conversion process can be time consuming.
1189 @item --gap-fill @var{val}
1190 Fill gaps between sections with @var{val}. This operation applies to
1191 the @emph{load address} (LMA) of the sections. It is done by increasing
1192 the size of the section with the lower address, and filling in the extra
1193 space created with @var{val}.
1195 @item --pad-to @var{address}
1196 Pad the output file up to the load address @var{address}. This is
1197 done by increasing the size of the last section. The extra space is
1198 filled in with the value specified by @option{--gap-fill} (default zero).
1200 @item --set-start @var{val}
1201 Set the start address of the new file to @var{val}. Not all object file
1202 formats support setting the start address.
1204 @item --change-start @var{incr}
1205 @itemx --adjust-start @var{incr}
1206 @cindex changing start address
1207 Change the start address by adding @var{incr}. Not all object file
1208 formats support setting the start address.
1210 @item --change-addresses @var{incr}
1211 @itemx --adjust-vma @var{incr}
1212 @cindex changing object addresses
1213 Change the VMA and LMA addresses of all sections, as well as the start
1214 address, by adding @var{incr}. Some object file formats do not permit
1215 section addresses to be changed arbitrarily. Note that this does not
1216 relocate the sections; if the program expects sections to be loaded at a
1217 certain address, and this option is used to change the sections such
1218 that they are loaded at a different address, the program may fail.
1220 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1221 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1222 @cindex changing section address
1223 Set or change both the VMA address and the LMA address of the named
1224 @var{section}. If @samp{=} is used, the section address is set to
1225 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1226 section address. See the comments under @option{--change-addresses},
1227 above. If @var{section} does not exist in the input file, a warning will
1228 be issued, unless @option{--no-change-warnings} is used.
1230 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1231 @cindex changing section LMA
1232 Set or change the LMA address of the named @var{section}. The LMA
1233 address is the address where the section will be loaded into memory at
1234 program load time. Normally this is the same as the VMA address, which
1235 is the address of the section at program run time, but on some systems,
1236 especially those where a program is held in ROM, the two can be
1237 different. If @samp{=} is used, the section address is set to
1238 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1239 section address. See the comments under @option{--change-addresses},
1240 above. If @var{section} does not exist in the input file, a warning
1241 will be issued, unless @option{--no-change-warnings} is used.
1243 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1244 @cindex changing section VMA
1245 Set or change the VMA address of the named @var{section}. The VMA
1246 address is the address where the section will be located once the
1247 program has started executing. Normally this is the same as the LMA
1248 address, which is the address where the section will be loaded into
1249 memory, but on some systems, especially those where a program is held in
1250 ROM, the two can be different. If @samp{=} is used, the section address
1251 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1252 from the section address. See the comments under
1253 @option{--change-addresses}, above. If @var{section} does not exist in
1254 the input file, a warning will be issued, unless
1255 @option{--no-change-warnings} is used.
1257 @item --change-warnings
1258 @itemx --adjust-warnings
1259 If @option{--change-section-address} or @option{--change-section-lma} or
1260 @option{--change-section-vma} is used, and the named section does not
1261 exist, issue a warning. This is the default.
1263 @item --no-change-warnings
1264 @itemx --no-adjust-warnings
1265 Do not issue a warning if @option{--change-section-address} or
1266 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1267 if the named section does not exist.
1269 @item --set-section-flags @var{section}=@var{flags}
1270 Set the flags for the named section. The @var{flags} argument is a
1271 comma separated string of flag names. The recognized names are
1272 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1273 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1274 @samp{debug}. You can set the @samp{contents} flag for a section which
1275 does not have contents, but it is not meaningful to clear the
1276 @samp{contents} flag of a section which does have contents--just remove
1277 the section instead. Not all flags are meaningful for all object file
1280 @item --add-section @var{sectionname}=@var{filename}
1281 Add a new section named @var{sectionname} while copying the file. The
1282 contents of the new section are taken from the file @var{filename}. The
1283 size of the section will be the size of the file. This option only
1284 works on file formats which can support sections with arbitrary names.
1286 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1287 Rename a section from @var{oldname} to @var{newname}, optionally
1288 changing the section's flags to @var{flags} in the process. This has
1289 the advantage over usng a linker script to perform the rename in that
1290 the output stays as an object file and does not become a linked
1293 This option is particularly helpful when the input format is binary,
1294 since this will always create a section called .data. If for example,
1295 you wanted instead to create a section called .rodata containing binary
1296 data you could use the following command line to achieve it:
1299 objcopy -I binary -O <output_format> -B <architecture> \
1300 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1301 <input_binary_file> <output_object_file>
1304 @item --change-leading-char
1305 Some object file formats use special characters at the start of
1306 symbols. The most common such character is underscore, which compilers
1307 often add before every symbol. This option tells @command{objcopy} to
1308 change the leading character of every symbol when it converts between
1309 object file formats. If the object file formats use the same leading
1310 character, this option has no effect. Otherwise, it will add a
1311 character, or remove a character, or change a character, as
1314 @item --remove-leading-char
1315 If the first character of a global symbol is a special symbol leading
1316 character used by the object file format, remove the character. The
1317 most common symbol leading character is underscore. This option will
1318 remove a leading underscore from all global symbols. This can be useful
1319 if you want to link together objects of different file formats with
1320 different conventions for symbol names. This is different from
1321 @option{--change-leading-char} because it always changes the symbol name
1322 when appropriate, regardless of the object file format of the output
1325 @item --srec-len=@var{ival}
1326 Meaningful only for srec output. Set the maximum length of the Srecords
1327 being produced to @var{ival}. This length covers both address, data and
1330 @item --srec-forceS3
1331 Meaningful only for srec output. Avoid generation of S1/S2 records,
1332 creating S3-only record format.
1334 @item --redefine-sym @var{old}=@var{new}
1335 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1336 when one is trying link two things together for which you have no
1337 source, and there are name collisions.
1339 @item --redefine-syms=@var{filename}
1340 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1341 listed in the file @var{filename}. @var{filename} is simply a flat file,
1342 with one symbol pair per line. Line comments may be introduced by the hash
1343 character. This option may be given more than once.
1346 Change all global symbols in the file to be weak. This can be useful
1347 when building an object which will be linked against other objects using
1348 the @option{-R} option to the linker. This option is only effective when
1349 using an object file format which supports weak symbols.
1351 @item --keep-symbols=@var{filename}
1352 Apply @option{--keep-symbol} option to each symbol listed in the file
1353 @var{filename}. @var{filename} is simply a flat file, with one symbol
1354 name per line. Line comments may be introduced by the hash character.
1355 This option may be given more than once.
1357 @item --strip-symbols=@var{filename}
1358 Apply @option{--strip-symbol} option to each symbol listed in the file
1359 @var{filename}. @var{filename} is simply a flat file, with one symbol
1360 name per line. Line comments may be introduced by the hash character.
1361 This option may be given more than once.
1363 @item --strip-unneeded-symbols=@var{filename}
1364 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1365 the file @var{filename}. @var{filename} is simply a flat file, with one
1366 symbol name per line. Line comments may be introduced by the hash
1367 character. This option may be given more than once.
1369 @item --keep-global-symbols=@var{filename}
1370 Apply @option{--keep-global-symbol} option to each symbol listed in the
1371 file @var{filename}. @var{filename} is simply a flat file, with one
1372 symbol name per line. Line comments may be introduced by the hash
1373 character. This option may be given more than once.
1375 @item --localize-symbols=@var{filename}
1376 Apply @option{--localize-symbol} option to each symbol listed in the file
1377 @var{filename}. @var{filename} is simply a flat file, with one symbol
1378 name per line. Line comments may be introduced by the hash character.
1379 This option may be given more than once.
1381 @item --globalize-symbols=@var{filename}
1382 Apply @option{--globalize-symbol} option to each symbol listed in the file
1383 @var{filename}. @var{filename} is simply a flat file, with one symbol
1384 name per line. Line comments may be introduced by the hash character.
1385 This option may be given more than once.
1387 @item --weaken-symbols=@var{filename}
1388 Apply @option{--weaken-symbol} option to each symbol listed in the file
1389 @var{filename}. @var{filename} is simply a flat file, with one symbol
1390 name per line. Line comments may be introduced by the hash character.
1391 This option may be given more than once.
1393 @item --alt-machine-code=@var{index}
1394 If the output architecture has alternate machine codes, use the
1395 @var{index}th code instead of the default one. This is useful in case
1396 a machine is assigned an official code and the tool-chain adopts the
1397 new code, but other applications still depend on the original code
1400 @item --writable-text
1401 Mark the output text as writable. This option isn't meaningful for all
1402 object file formats.
1404 @item --readonly-text
1405 Make the output text write protected. This option isn't meaningful for all
1406 object file formats.
1409 Mark the output file as demand paged. This option isn't meaningful for all
1410 object file formats.
1413 Mark the output file as impure. This option isn't meaningful for all
1414 object file formats.
1416 @item --prefix-symbols=@var{string}
1417 Prefix all symbols in the output file with @var{string}.
1419 @item --prefix-sections=@var{string}
1420 Prefix all section names in the output file with @var{string}.
1422 @item --prefix-alloc-sections=@var{string}
1423 Prefix all the names of all allocated sections in the output file with
1426 @item --add-gnu-debuglink=@var{path-to-file}
1427 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1428 and adds it to the output file.
1430 @item --only-keep-debug
1431 Strip a file, removing contents of any sections that would not be
1432 stripped by @option{--strip-debug} and leaving the debugging sections
1435 The intention is that this option will be used in conjunction with
1436 @option{--add-gnu-debuglink} to create a two part executable. One a
1437 stripped binary which will occupy less space in RAM and in a
1438 distribution and the second a debugging information file which is only
1439 needed if debugging abilities are required. The suggested procedure
1440 to create these files is as follows:
1443 @item Link the executable as normal. Assuming that is is called
1445 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1446 create a file containing the debugging info.
1447 @item Run @code{objcopy --strip-debug foo} to create a
1448 stripped executable.
1449 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1450 to add a link to the debugging info into the stripped executable.
1453 Note - the choice of @code{.dbg} as an extension for the debug info
1454 file is arbitrary. Also the @code{--only-keep-debug} step is
1455 optional. You could instead do this:
1458 @item Link the executable as normal.
1459 @item Copy @code{foo} to @code{foo.full}
1460 @item Run @code{objcopy --strip-debug foo}
1461 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1464 i.e. the file pointed to by the @option{--add-gnu-debuglink} can be the
1465 full executable. It does not have to be a file created by the
1466 @option{--only-keep-debug} switch.
1470 Show the version number of @command{objcopy}.
1474 Verbose output: list all object files modified. In the case of
1475 archives, @samp{objcopy -V} lists all members of the archive.
1478 Show a summary of the options to @command{objcopy}.
1481 Display a list showing all architectures and object formats available.
1487 @c man begin SEEALSO objcopy
1488 ld(1), objdump(1), and the Info entries for @file{binutils}.
1495 @cindex object file information
1498 @c man title objdump display information from object files.
1501 @c man begin SYNOPSIS objdump
1502 objdump [@option{-a}|@option{--archive-headers}]
1503 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1504 [@option{-C}|@option{--demangle}[=@var{style}] ]
1505 [@option{-d}|@option{--disassemble}]
1506 [@option{-D}|@option{--disassemble-all}]
1507 [@option{-z}|@option{--disassemble-zeroes}]
1508 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1509 [@option{-f}|@option{--file-headers}]
1510 [@option{--file-start-context}]
1511 [@option{-g}|@option{--debugging}]
1512 [@option{-e}|@option{--debugging-tags}]
1513 [@option{-h}|@option{--section-headers}|@option{--headers}]
1514 [@option{-i}|@option{--info}]
1515 [@option{-j} @var{section}|@option{--section=}@var{section}]
1516 [@option{-l}|@option{--line-numbers}]
1517 [@option{-S}|@option{--source}]
1518 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1519 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1520 [@option{-p}|@option{--private-headers}]
1521 [@option{-r}|@option{--reloc}]
1522 [@option{-R}|@option{--dynamic-reloc}]
1523 [@option{-s}|@option{--full-contents}]
1524 [@option{-G}|@option{--stabs}]
1525 [@option{-t}|@option{--syms}]
1526 [@option{-T}|@option{--dynamic-syms}]
1527 [@option{-x}|@option{--all-headers}]
1528 [@option{-w}|@option{--wide}]
1529 [@option{--start-address=}@var{address}]
1530 [@option{--stop-address=}@var{address}]
1531 [@option{--prefix-addresses}]
1532 [@option{--[no-]show-raw-insn}]
1533 [@option{--adjust-vma=}@var{offset}]
1534 [@option{--special-syms}]
1535 [@option{-V}|@option{--version}]
1536 [@option{-H}|@option{--help}]
1537 @var{objfile}@dots{}
1541 @c man begin DESCRIPTION objdump
1543 @command{objdump} displays information about one or more object files.
1544 The options control what particular information to display. This
1545 information is mostly useful to programmers who are working on the
1546 compilation tools, as opposed to programmers who just want their
1547 program to compile and work.
1549 @var{objfile}@dots{} are the object files to be examined. When you
1550 specify archives, @command{objdump} shows information on each of the member
1555 @c man begin OPTIONS objdump
1557 The long and short forms of options, shown here as alternatives, are
1558 equivalent. At least one option from the list
1559 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1563 @itemx --archive-header
1564 @cindex archive headers
1565 If any of the @var{objfile} files are archives, display the archive
1566 header information (in a format similar to @samp{ls -l}). Besides the
1567 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1568 the object file format of each archive member.
1570 @item --adjust-vma=@var{offset}
1571 @cindex section addresses in objdump
1572 @cindex VMA in objdump
1573 When dumping information, first add @var{offset} to all the section
1574 addresses. This is useful if the section addresses do not correspond to
1575 the symbol table, which can happen when putting sections at particular
1576 addresses when using a format which can not represent section addresses,
1579 @item -b @var{bfdname}
1580 @itemx --target=@var{bfdname}
1581 @cindex object code format
1582 Specify that the object-code format for the object files is
1583 @var{bfdname}. This option may not be necessary; @var{objdump} can
1584 automatically recognize many formats.
1588 objdump -b oasys -m vax -h fu.o
1591 displays summary information from the section headers (@option{-h}) of
1592 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1593 file in the format produced by Oasys compilers. You can list the
1594 formats available with the @option{-i} option.
1595 @xref{Target Selection}, for more information.
1598 @itemx --demangle[=@var{style}]
1599 @cindex demangling in objdump
1600 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1601 Besides removing any initial underscore prepended by the system, this
1602 makes C++ function names readable. Different compilers have different
1603 mangling styles. The optional demangling style argument can be used to
1604 choose an appropriate demangling style for your compiler. @xref{c++filt},
1605 for more information on demangling.
1609 Display debugging information. This attempts to parse debugging
1610 information stored in the file and print it out using a C like syntax.
1611 Only certain types of debugging information have been implemented.
1612 Some other types are supported by @command{readelf -w}.
1616 @itemx --debugging-tags
1617 Like @option{-g}, but the information is generated in a format compatible
1621 @itemx --disassemble
1622 @cindex disassembling object code
1623 @cindex machine instructions
1624 Display the assembler mnemonics for the machine instructions from
1625 @var{objfile}. This option only disassembles those sections which are
1626 expected to contain instructions.
1629 @itemx --disassemble-all
1630 Like @option{-d}, but disassemble the contents of all sections, not just
1631 those expected to contain instructions.
1633 @item --prefix-addresses
1634 When disassembling, print the complete address on each line. This is
1635 the older disassembly format.
1639 @itemx --endian=@{big|little@}
1641 @cindex disassembly endianness
1642 Specify the endianness of the object files. This only affects
1643 disassembly. This can be useful when disassembling a file format which
1644 does not describe endianness information, such as S-records.
1647 @itemx --file-headers
1648 @cindex object file header
1649 Display summary information from the overall header of
1650 each of the @var{objfile} files.
1652 @item --file-start-context
1653 @cindex source code context
1654 Specify that when displaying interlisted source code/disassembly
1655 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1656 context to the start of the file.
1659 @itemx --section-headers
1661 @cindex section headers
1662 Display summary information from the section headers of the
1665 File segments may be relocated to nonstandard addresses, for example by
1666 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1667 @command{ld}. However, some object file formats, such as a.out, do not
1668 store the starting address of the file segments. In those situations,
1669 although @command{ld} relocates the sections correctly, using @samp{objdump
1670 -h} to list the file section headers cannot show the correct addresses.
1671 Instead, it shows the usual addresses, which are implicit for the
1676 Print a summary of the options to @command{objdump} and exit.
1680 @cindex architectures available
1681 @cindex object formats available
1682 Display a list showing all architectures and object formats available
1683 for specification with @option{-b} or @option{-m}.
1686 @itemx --section=@var{name}
1687 @cindex section information
1688 Display information only for section @var{name}.
1691 @itemx --line-numbers
1692 @cindex source filenames for object files
1693 Label the display (using debugging information) with the filename and
1694 source line numbers corresponding to the object code or relocs shown.
1695 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1697 @item -m @var{machine}
1698 @itemx --architecture=@var{machine}
1699 @cindex architecture
1700 @cindex disassembly architecture
1701 Specify the architecture to use when disassembling object files. This
1702 can be useful when disassembling object files which do not describe
1703 architecture information, such as S-records. You can list the available
1704 architectures with the @option{-i} option.
1706 @item -M @var{options}
1707 @itemx --disassembler-options=@var{options}
1708 Pass target specific information to the disassembler. Only supported on
1709 some targets. If it is necessary to specify more than one
1710 disassembler option then multiple @option{-M} options can be used or
1711 can be placed together into a comma separated list.
1713 If the target is an ARM architecture then this switch can be used to
1714 select which register name set is used during disassembler. Specifying
1715 @option{-M reg-name-std} (the default) will select the register names as
1716 used in ARM's instruction set documentation, but with register 13 called
1717 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1718 @option{-M reg-names-apcs} will select the name set used by the ARM
1719 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1720 just use @samp{r} followed by the register number.
1722 There are also two variants on the APCS register naming scheme enabled
1723 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1724 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1725 with the normal register names or the special register names).
1727 This option can also be used for ARM architectures to force the
1728 disassembler to interpret all instructions as Thumb instructions by
1729 using the switch @option{--disassembler-options=force-thumb}. This can be
1730 useful when attempting to disassemble thumb code produced by other
1733 For the x86, some of the options duplicate functions of the @option{-m}
1734 switch, but allow finer grained control. Multiple selections from the
1735 following may be specified as a comma separated string.
1736 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1737 the given architecture. @option{intel} and @option{att} select between
1738 intel syntax mode and AT&T syntax mode. @option{addr32},
1739 @option{addr16}, @option{data32} and @option{data16} specify the default
1740 address size and operand size. These four options will be overridden if
1741 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1742 option string. Lastly, @option{suffix}, when in AT&T mode,
1743 instructs the disassembler to print a mnemonic suffix even when the
1744 suffix could be inferred by the operands.
1746 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1747 disassembly of BookE instructions. @option{32} and @option{64} select
1748 PowerPC and PowerPC64 disassembly, respectively.
1750 For MIPS, this option controls the printing of instruction mneumonic
1751 names and register names in disassembled instructions. Multiple
1752 selections from the following may be specified as a comma separated
1753 string, and invalid options are ignored:
1757 Print the 'raw' instruction mneumonic instead of some pseudo
1758 instruction mneumonic. I.E. print 'daddu' or 'or' instead of 'move',
1759 'sll' instead of 'nop', etc.
1761 @item gpr-names=@var{ABI}
1762 Print GPR (general-purpose register) names as appropriate
1763 for the specified ABI. By default, GPR names are selected according to
1764 the ABI of the binary being disassembled.
1766 @item fpr-names=@var{ABI}
1767 Print FPR (floating-point register) names as
1768 appropriate for the specified ABI. By default, FPR numbers are printed
1771 @item cp0-names=@var{ARCH}
1772 Print CP0 (system control coprocessor; coprocessor 0) register names
1773 as appropriate for the CPU or architecture specified by
1774 @var{ARCH}. By default, CP0 register names are selected according to
1775 the architecture and CPU of the binary being disassembled.
1777 @item hwr-names=@var{ARCH}
1778 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1779 as appropriate for the CPU or architecture specified by
1780 @var{ARCH}. By default, HWR names are selected according to
1781 the architecture and CPU of the binary being disassembled.
1783 @item reg-names=@var{ABI}
1784 Print GPR and FPR names as appropriate for the selected ABI.
1786 @item reg-names=@var{ARCH}
1787 Print CPU-specific register names (CP0 register and HWR names)
1788 as appropriate for the selected CPU or architecture.
1791 For any of the options listed above, @var{ABI} or
1792 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1793 rather than names, for the selected types of registers.
1794 You can list the available values of @var{ABI} and @var{ARCH} using
1795 the @option{--help} option.
1797 For VAX, you can specify function entry addresses with @option{-M
1798 entry:0xf00ba}. You can use this multiple times to properly
1799 disassemble VAX binary files that don't contain symbol tables (like
1800 ROM dumps). In these cases, the function entry mask would otherwise
1801 be decoded as VAX instructions, which would probably lead the the rest
1802 of the function being wrongly disassembled.
1805 @itemx --private-headers
1806 Print information that is specific to the object file format. The exact
1807 information printed depends upon the object file format. For some
1808 object file formats, no additional information is printed.
1812 @cindex relocation entries, in object file
1813 Print the relocation entries of the file. If used with @option{-d} or
1814 @option{-D}, the relocations are printed interspersed with the
1818 @itemx --dynamic-reloc
1819 @cindex dynamic relocation entries, in object file
1820 Print the dynamic relocation entries of the file. This is only
1821 meaningful for dynamic objects, such as certain types of shared
1825 @itemx --full-contents
1826 @cindex sections, full contents
1827 @cindex object file sections
1828 Display the full contents of any sections requested. By default all
1829 non-empty sections are displayed.
1833 @cindex source disassembly
1834 @cindex disassembly, with source
1835 Display source code intermixed with disassembly, if possible. Implies
1838 @item --show-raw-insn
1839 When disassembling instructions, print the instruction in hex as well as
1840 in symbolic form. This is the default except when
1841 @option{--prefix-addresses} is used.
1843 @item --no-show-raw-insn
1844 When disassembling instructions, do not print the instruction bytes.
1845 This is the default when @option{--prefix-addresses} is used.
1851 @cindex debug symbols
1852 @cindex ELF object file format
1853 Display the full contents of any sections requested. Display the
1854 contents of the .stab and .stab.index and .stab.excl sections from an
1855 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1856 @code{.stab} debugging symbol-table entries are carried in an ELF
1857 section. In most other file formats, debugging symbol-table entries are
1858 interleaved with linkage symbols, and are visible in the @option{--syms}
1861 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1862 Overview,stabs.info, The ``stabs'' debug format}.
1865 @item --start-address=@var{address}
1866 @cindex start-address
1867 Start displaying data at the specified address. This affects the output
1868 of the @option{-d}, @option{-r} and @option{-s} options.
1870 @item --stop-address=@var{address}
1871 @cindex stop-address
1872 Stop displaying data at the specified address. This affects the output
1873 of the @option{-d}, @option{-r} and @option{-s} options.
1877 @cindex symbol table entries, printing
1878 Print the symbol table entries of the file.
1879 This is similar to the information provided by the @samp{nm} program.
1882 @itemx --dynamic-syms
1883 @cindex dynamic symbol table entries, printing
1884 Print the dynamic symbol table entries of the file. This is only
1885 meaningful for dynamic objects, such as certain types of shared
1886 libraries. This is similar to the information provided by the @samp{nm}
1887 program when given the @option{-D} (@option{--dynamic}) option.
1889 @item --special-syms
1890 When displaying symbols include those which the target considers to be
1891 special in some way and which would not normally be of interest to the
1896 Print the version number of @command{objdump} and exit.
1899 @itemx --all-headers
1900 @cindex all header information, object file
1901 @cindex header information, all
1902 Display all available header information, including the symbol table and
1903 relocation entries. Using @option{-x} is equivalent to specifying all of
1904 @option{-a -f -h -p -r -t}.
1908 @cindex wide output, printing
1909 Format some lines for output devices that have more than 80 columns.
1910 Also do not truncate symbol names when they are displayed.
1913 @itemx --disassemble-zeroes
1914 Normally the disassembly output will skip blocks of zeroes. This
1915 option directs the disassembler to disassemble those blocks, just like
1922 @c man begin SEEALSO objdump
1923 nm(1), readelf(1), and the Info entries for @file{binutils}.
1931 @cindex archive contents
1932 @cindex symbol index
1934 @c man title ranlib generate index to archive.
1937 @c man begin SYNOPSIS ranlib
1938 ranlib [@option{-vV}] @var{archive}
1942 @c man begin DESCRIPTION ranlib
1944 @command{ranlib} generates an index to the contents of an archive and
1945 stores it in the archive. The index lists each symbol defined by a
1946 member of an archive that is a relocatable object file.
1948 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1950 An archive with such an index speeds up linking to the library and
1951 allows routines in the library to call each other without regard to
1952 their placement in the archive.
1954 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1955 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1960 @c man begin OPTIONS ranlib
1966 Show the version number of @command{ranlib}.
1972 @c man begin SEEALSO ranlib
1973 ar(1), nm(1), and the Info entries for @file{binutils}.
1981 @cindex section sizes
1983 @c man title size list section sizes and total size.
1986 @c man begin SYNOPSIS size
1987 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1989 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1990 [@option{-t}|@option{--totals}]
1991 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1992 [@var{objfile}@dots{}]
1996 @c man begin DESCRIPTION size
1998 The @sc{gnu} @command{size} utility lists the section sizes---and the total
1999 size---for each of the object or archive files @var{objfile} in its
2000 argument list. By default, one line of output is generated for each
2001 object file or each module in an archive.
2003 @var{objfile}@dots{} are the object files to be examined.
2004 If none are specified, the file @code{a.out} will be used.
2008 @c man begin OPTIONS size
2010 The command line options have the following meanings:
2015 @itemx --format=@var{compatibility}
2016 @cindex @command{size} display format
2017 Using one of these options, you can choose whether the output from @sc{gnu}
2018 @command{size} resembles output from System V @command{size} (using @option{-A},
2019 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2020 @option{--format=berkeley}). The default is the one-line format similar to
2022 @c Bonus for doc-source readers: you can also say --format=strange (or
2023 @c anything else that starts with 's') for sysv, and --format=boring (or
2024 @c anything else that starts with 'b') for Berkeley.
2026 Here is an example of the Berkeley (default) format of output from
2029 $ size --format=Berkeley ranlib size
2030 text data bss dec hex filename
2031 294880 81920 11592 388392 5ed28 ranlib
2032 294880 81920 11888 388688 5ee50 size
2036 This is the same data, but displayed closer to System V conventions:
2039 $ size --format=SysV ranlib size
2057 Show a summary of acceptable arguments and options.
2062 @itemx --radix=@var{number}
2063 @cindex @command{size} number format
2064 @cindex radix for section sizes
2065 Using one of these options, you can control whether the size of each
2066 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2067 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2068 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2069 values (8, 10, 16) are supported. The total size is always given in two
2070 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2071 octal and hexadecimal if you're using @option{-o}.
2075 Show totals of all objects listed (Berkeley format listing mode only).
2077 @item --target=@var{bfdname}
2078 @cindex object code format
2079 Specify that the object-code format for @var{objfile} is
2080 @var{bfdname}. This option may not be necessary; @command{size} can
2081 automatically recognize many formats.
2082 @xref{Target Selection}, for more information.
2086 Display the version number of @command{size}.
2092 @c man begin SEEALSO size
2093 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2100 @cindex listings strings
2101 @cindex printing strings
2102 @cindex strings, printing
2104 @c man title strings print the strings of printable characters in files.
2107 @c man begin SYNOPSIS strings
2108 strings [@option{-afov}] [@option{-}@var{min-len}]
2109 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2110 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2111 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2112 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2113 [@option{--target=}@var{bfdname}]
2114 [@option{--help}] [@option{--version}] @var{file}@dots{}
2118 @c man begin DESCRIPTION strings
2120 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2121 character sequences that are at least 4 characters long (or the number
2122 given with the options below) and are followed by an unprintable
2123 character. By default, it only prints the strings from the initialized
2124 and loaded sections of object files; for other types of files, it prints
2125 the strings from the whole file.
2127 @command{strings} is mainly useful for determining the contents of non-text
2132 @c man begin OPTIONS strings
2138 Do not scan only the initialized and loaded sections of object files;
2139 scan the whole files.
2142 @itemx --print-file-name
2143 Print the name of the file before each string.
2146 Print a summary of the program usage on the standard output and exit.
2148 @item -@var{min-len}
2149 @itemx -n @var{min-len}
2150 @itemx --bytes=@var{min-len}
2151 Print sequences of characters that are at least @var{min-len} characters
2152 long, instead of the default 4.
2155 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2156 act like @samp{-t d} instead. Since we can not be compatible with both
2157 ways, we simply chose one.
2159 @item -t @var{radix}
2160 @itemx --radix=@var{radix}
2161 Print the offset within the file before each string. The single
2162 character argument specifies the radix of the offset---@samp{o} for
2163 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2165 @item -e @var{encoding}
2166 @itemx --encoding=@var{encoding}
2167 Select the character encoding of the strings that are to be found.
2168 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2169 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2170 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2171 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2172 littleendian. Useful for finding wide character strings.
2174 @item --target=@var{bfdname}
2175 @cindex object code format
2176 Specify an object code format other than your system's default format.
2177 @xref{Target Selection}, for more information.
2181 Print the program version number on the standard output and exit.
2187 @c man begin SEEALSO strings
2188 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2189 and the Info entries for @file{binutils}.
2197 @cindex removing symbols
2198 @cindex discarding symbols
2199 @cindex symbols, discarding
2201 @c man title strip Discard symbols from object files.
2204 @c man begin SYNOPSIS strip
2205 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2206 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2207 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2208 [@option{-s}|@option{--strip-all}]
2209 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2210 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2211 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2212 [@option{-w}|@option{--wildcard}]
2213 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2214 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2215 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2216 [@option{--only-keep-debug}]
2217 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2218 [@option{--help}] [@option{--info}]
2219 @var{objfile}@dots{}
2223 @c man begin DESCRIPTION strip
2225 @sc{gnu} @command{strip} discards all symbols from object files
2226 @var{objfile}. The list of object files may include archives.
2227 At least one object file must be given.
2229 @command{strip} modifies the files named in its argument,
2230 rather than writing modified copies under different names.
2234 @c man begin OPTIONS strip
2237 @item -F @var{bfdname}
2238 @itemx --target=@var{bfdname}
2239 Treat the original @var{objfile} as a file with the object
2240 code format @var{bfdname}, and rewrite it in the same format.
2241 @xref{Target Selection}, for more information.
2244 Show a summary of the options to @command{strip} and exit.
2247 Display a list showing all architectures and object formats available.
2249 @item -I @var{bfdname}
2250 @itemx --input-target=@var{bfdname}
2251 Treat the original @var{objfile} as a file with the object
2252 code format @var{bfdname}.
2253 @xref{Target Selection}, for more information.
2255 @item -O @var{bfdname}
2256 @itemx --output-target=@var{bfdname}
2257 Replace @var{objfile} with a file in the output format @var{bfdname}.
2258 @xref{Target Selection}, for more information.
2260 @item -R @var{sectionname}
2261 @itemx --remove-section=@var{sectionname}
2262 Remove any section named @var{sectionname} from the output file. This
2263 option may be given more than once. Note that using this option
2264 inappropriately may make the output file unusable.
2273 @itemx --strip-debug
2274 Remove debugging symbols only.
2276 @item --strip-unneeded
2277 Remove all symbols that are not needed for relocation processing.
2279 @item -K @var{symbolname}
2280 @itemx --keep-symbol=@var{symbolname}
2281 When stripping symbols, keep symbol @var{symbolname} even if it would
2282 normally be stripped. This option may be given more than once.
2284 @item -N @var{symbolname}
2285 @itemx --strip-symbol=@var{symbolname}
2286 Remove symbol @var{symbolname} from the source file. This option may be
2287 given more than once, and may be combined with strip options other than
2291 Put the stripped output in @var{file}, rather than replacing the
2292 existing file. When this argument is used, only one @var{objfile}
2293 argument may be specified.
2296 @itemx --preserve-dates
2297 Preserve the access and modification dates of the file.
2301 Permit regular expressions in @var{symbolname}s used in other command
2302 line options. The question mark (?), asterisk (*), backslash (\) and
2303 square brackets ([]) operators can be used anywhere in the symbol
2304 name. If the first character of the symbol name is the exclamation
2305 point (!) then the sense of the switch is reversed for that symbol.
2312 would cause strip to only keep symbols that start with the letters
2313 ``fo'', but to discard the symbol ``foo''.
2316 @itemx --discard-all
2317 Remove non-global symbols.
2320 @itemx --discard-locals
2321 Remove compiler-generated local symbols.
2322 (These usually start with @samp{L} or @samp{.}.)
2324 @item --only-keep-debug
2325 Strip a file, removing any sections that would be stripped by
2326 @option{--strip-debug} and leaving the debugging sections.
2328 The intention is that this option will be used in conjunction with
2329 @option{--add-gnu-debuglink} to create a two part executable. One a
2330 stripped binary which will occupy less space in RAM and in a
2331 distribution and the second a debugging information file which is only
2332 needed if debugging abilities are required. The suggested procedure
2333 to create these files is as follows:
2336 @item Link the executable as normal. Assuming that is is called
2338 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2339 create a file containing the debugging info.
2340 @item Run @code{objcopy --strip-debug foo} to create a
2341 stripped executable.
2342 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2343 to add a link to the debugging info into the stripped executable.
2346 Note - the choice of @code{.dbg} as an extension for the debug info
2347 file is arbitrary. Also the @code{--only-keep-debug} step is
2348 optional. You could instead do this:
2351 @item Link the executable as normal.
2352 @item Copy @code{foo} to @code{foo.full}
2353 @item Run @code{strip --strip-debug foo}
2354 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2357 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2358 full executable. It does not have to be a file created by the
2359 @option{--only-keep-debug} switch.
2363 Show the version number for @command{strip}.
2367 Verbose output: list all object files modified. In the case of
2368 archives, @samp{strip -v} lists all members of the archive.
2374 @c man begin SEEALSO strip
2375 the Info entries for @file{binutils}.
2379 @node c++filt, addr2line, strip, Top
2383 @cindex demangling C++ symbols
2385 @c man title cxxfilt Demangle C++ and Java symbols.
2388 @c man begin SYNOPSIS cxxfilt
2389 c++filt [@option{-_}|@option{--strip-underscores}]
2390 [@option{-j}|@option{--java}]
2391 [@option{-n}|@option{--no-strip-underscores}]
2392 [@option{-p}|@option{--no-params}]
2393 [@option{-s} @var{format}|@option{--format=}@var{format}]
2394 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2398 @c man begin DESCRIPTION cxxfilt
2401 The C++ and Java languages provides function overloading, which means
2402 that you can write many functions with the same name (providing each
2403 takes parameters of different types). All C++ and Java function names
2404 are encoded into a low-level assembly label (this process is known as
2405 @dfn{mangling}). The @command{c++filt}
2406 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2407 MS-DOS this program is named @command{CXXFILT}.}
2408 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2409 names into user-level names so that the linker can keep these overloaded
2410 functions from clashing.
2412 Every alphanumeric word (consisting of letters, digits, underscores,
2413 dollars, or periods) seen in the input is a potential label. If the
2414 label decodes into a C++ name, the C++ name replaces the low-level
2417 You can use @command{c++filt} to decipher individual symbols:
2420 c++filt @var{symbol}
2423 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2424 names from the standard input and writes the demangled names to the
2425 standard output. All results are printed on the standard output.
2429 @c man begin OPTIONS cxxfilt
2433 @itemx --strip-underscores
2434 On some systems, both the C and C++ compilers put an underscore in front
2435 of every name. For example, the C name @code{foo} gets the low-level
2436 name @code{_foo}. This option removes the initial underscore. Whether
2437 @command{c++filt} removes the underscore by default is target dependent.
2441 Prints demangled names using Java syntax. The default is to use C++
2445 @itemx --no-strip-underscores
2446 Do not remove the initial underscore.
2450 When demangling the name of a function, do not display the types of
2451 the function's parameters.
2453 @item -s @var{format}
2454 @itemx --format=@var{format}
2455 @command{c++filt} can decode various methods of mangling, used by
2456 different compilers. The argument to this option selects which
2461 Automatic selection based on executable (the default method)
2463 the one used by the @sc{gnu} C++ compiler (g++)
2465 the one used by the Lucid compiler (lcc)
2467 the one specified by the C++ Annotated Reference Manual
2469 the one used by the HP compiler (aCC)
2471 the one used by the EDG compiler
2473 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2475 the one used by the @sc{gnu} Java compiler (gcj)
2477 the one used by the @sc{gnu} Ada compiler (GNAT).
2481 Print a summary of the options to @command{c++filt} and exit.
2484 Print the version number of @command{c++filt} and exit.
2490 @c man begin SEEALSO cxxfilt
2491 the Info entries for @file{binutils}.
2496 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2497 user interface are subject to change in future releases. In particular,
2498 a command-line option may be required in the the future to decode a name
2499 passed as an argument on the command line; in other words,
2502 c++filt @var{symbol}
2506 may in a future release become
2509 c++filt @var{option} @var{symbol}
2517 @cindex address to file name and line number
2519 @c man title addr2line convert addresses into file names and line numbers.
2522 @c man begin SYNOPSIS addr2line
2523 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2524 [@option{-C}|@option{--demangle}[=@var{style}]]
2525 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2526 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2527 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2532 @c man begin DESCRIPTION addr2line
2534 @command{addr2line} translates program addresses into file names and line
2535 numbers. Given an address and an executable, it uses the debugging
2536 information in the executable to figure out which file name and line
2537 number are associated with a given address.
2539 The executable to use is specified with the @option{-e} option. The
2540 default is the file @file{a.out}.
2542 @command{addr2line} has two modes of operation.
2544 In the first, hexadecimal addresses are specified on the command line,
2545 and @command{addr2line} displays the file name and line number for each
2548 In the second, @command{addr2line} reads hexadecimal addresses from
2549 standard input, and prints the file name and line number for each
2550 address on standard output. In this mode, @command{addr2line} may be used
2551 in a pipe to convert dynamically chosen addresses.
2553 The format of the output is @samp{FILENAME:LINENO}. The file name and
2554 line number for each address is printed on a separate line. If the
2555 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2556 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2557 containing the address.
2559 If the file name or function name can not be determined,
2560 @command{addr2line} will print two question marks in their place. If the
2561 line number can not be determined, @command{addr2line} will print 0.
2565 @c man begin OPTIONS addr2line
2567 The long and short forms of options, shown here as alternatives, are
2571 @item -b @var{bfdname}
2572 @itemx --target=@var{bfdname}
2573 @cindex object code format
2574 Specify that the object-code format for the object files is
2578 @itemx --demangle[=@var{style}]
2579 @cindex demangling in objdump
2580 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2581 Besides removing any initial underscore prepended by the system, this
2582 makes C++ function names readable. Different compilers have different
2583 mangling styles. The optional demangling style argument can be used to
2584 choose an appropriate demangling style for your compiler. @xref{c++filt},
2585 for more information on demangling.
2587 @item -e @var{filename}
2588 @itemx --exe=@var{filename}
2589 Specify the name of the executable for which addresses should be
2590 translated. The default file is @file{a.out}.
2594 Display function names as well as file and line number information.
2598 Display only the base of each file name.
2604 @c man begin SEEALSO addr2line
2605 Info entries for @file{binutils}.
2612 @command{nlmconv} converts a relocatable object file into a NetWare
2616 @command{nlmconv} currently works with @samp{i386} object
2617 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2618 object files in @sc{elf}, or @code{a.out} format@footnote{
2619 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2620 format in the Binary File Descriptor library. It has only been tested
2621 with the above formats.}.
2625 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2626 utilities, since it is only useful for NLM targets.
2629 @c man title nlmconv converts object code into an NLM.
2632 @c man begin SYNOPSIS nlmconv
2633 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2634 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2635 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2636 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2637 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2638 @var{infile} @var{outfile}
2642 @c man begin DESCRIPTION nlmconv
2644 @command{nlmconv} converts the relocatable @samp{i386} object file
2645 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2646 reading @var{headerfile} for NLM header information. For instructions
2647 on writing the NLM command file language used in header files, see the
2648 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2649 Development and Tools Overview}, which is part of the NLM Software
2650 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2651 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2654 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2657 @command{nlmconv} can perform a link step. In other words, you can list
2658 more than one object file for input if you list them in the definitions
2659 file (rather than simply specifying one input file on the command line).
2660 In this case, @command{nlmconv} calls the linker for you.
2664 @c man begin OPTIONS nlmconv
2667 @item -I @var{bfdname}
2668 @itemx --input-target=@var{bfdname}
2669 Object format of the input file. @command{nlmconv} can usually determine
2670 the format of a given file (so no default is necessary).
2671 @xref{Target Selection}, for more information.
2673 @item -O @var{bfdname}
2674 @itemx --output-target=@var{bfdname}
2675 Object format of the output file. @command{nlmconv} infers the output
2676 format based on the input format, e.g. for a @samp{i386} input file the
2677 output format is @samp{nlm32-i386}.
2678 @xref{Target Selection}, for more information.
2680 @item -T @var{headerfile}
2681 @itemx --header-file=@var{headerfile}
2682 Reads @var{headerfile} for NLM header information. For instructions on
2683 writing the NLM command file language used in header files, see@ see the
2684 @samp{linkers} section, of the @cite{NLM Development and Tools
2685 Overview}, which is part of the NLM Software Developer's Kit, available
2690 Displays (on standard error) the linker command line used by @command{nlmconv}.
2692 @item -l @var{linker}
2693 @itemx --linker=@var{linker}
2694 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2699 Prints a usage summary.
2703 Prints the version number for @command{nlmconv}.
2709 @c man begin SEEALSO nlmconv
2710 the Info entries for @file{binutils}.
2717 @command{windres} may be used to manipulate Windows resources.
2720 @emph{Warning:} @command{windres} is not always built as part of the binary
2721 utilities, since it is only useful for Windows targets.
2724 @c man title windres manipulate Windows resources.
2727 @c man begin SYNOPSIS windres
2728 windres [options] [input-file] [output-file]
2732 @c man begin DESCRIPTION windres
2734 @command{windres} reads resources from an input file and copies them into
2735 an output file. Either file may be in one of three formats:
2739 A text format read by the Resource Compiler.
2742 A binary format generated by the Resource Compiler.
2745 A COFF object or executable.
2748 The exact description of these different formats is available in
2749 documentation from Microsoft.
2751 When @command{windres} converts from the @code{rc} format to the @code{res}
2752 format, it is acting like the Windows Resource Compiler. When
2753 @command{windres} converts from the @code{res} format to the @code{coff}
2754 format, it is acting like the Windows @code{CVTRES} program.
2756 When @command{windres} generates an @code{rc} file, the output is similar
2757 but not identical to the format expected for the input. When an input
2758 @code{rc} file refers to an external filename, an output @code{rc} file
2759 will instead include the file contents.
2761 If the input or output format is not specified, @command{windres} will
2762 guess based on the file name, or, for the input file, the file contents.
2763 A file with an extension of @file{.rc} will be treated as an @code{rc}
2764 file, a file with an extension of @file{.res} will be treated as a
2765 @code{res} file, and a file with an extension of @file{.o} or
2766 @file{.exe} will be treated as a @code{coff} file.
2768 If no output file is specified, @command{windres} will print the resources
2769 in @code{rc} format to standard output.
2771 The normal use is for you to write an @code{rc} file, use @command{windres}
2772 to convert it to a COFF object file, and then link the COFF file into
2773 your application. This will make the resources described in the
2774 @code{rc} file available to Windows.
2778 @c man begin OPTIONS windres
2781 @item -i @var{filename}
2782 @itemx --input @var{filename}
2783 The name of the input file. If this option is not used, then
2784 @command{windres} will use the first non-option argument as the input file
2785 name. If there are no non-option arguments, then @command{windres} will
2786 read from standard input. @command{windres} can not read a COFF file from
2789 @item -o @var{filename}
2790 @itemx --output @var{filename}
2791 The name of the output file. If this option is not used, then
2792 @command{windres} will use the first non-option argument, after any used
2793 for the input file name, as the output file name. If there is no
2794 non-option argument, then @command{windres} will write to standard output.
2795 @command{windres} can not write a COFF file to standard output. Note,
2796 for compatability with @command{rc} the option @option{-fo} is also
2797 accepted, but its use is not recommended.
2799 @item -J @var{format}
2800 @itemx --input-format @var{format}
2801 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2802 @samp{coff}. If no input format is specified, @command{windres} will
2803 guess, as described above.
2805 @item -O @var{format}
2806 @itemx --output-format @var{format}
2807 The output format to generate. @var{format} may be @samp{res},
2808 @samp{rc}, or @samp{coff}. If no output format is specified,
2809 @command{windres} will guess, as described above.
2811 @item -F @var{target}
2812 @itemx --target @var{target}
2813 Specify the BFD format to use for a COFF file as input or output. This
2814 is a BFD target name; you can use the @option{--help} option to see a list
2815 of supported targets. Normally @command{windres} will use the default
2816 format, which is the first one listed by the @option{--help} option.
2818 @ref{Target Selection}.
2821 @item --preprocessor @var{program}
2822 When @command{windres} reads an @code{rc} file, it runs it through the C
2823 preprocessor first. This option may be used to specify the preprocessor
2824 to use, including any leading arguments. The default preprocessor
2825 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2827 @item -I @var{directory}
2828 @itemx --include-dir @var{directory}
2829 Specify an include directory to use when reading an @code{rc} file.
2830 @command{windres} will pass this to the preprocessor as an @option{-I}
2831 option. @command{windres} will also search this directory when looking for
2832 files named in the @code{rc} file. If the argument passed to this command
2833 matches any of the supported @var{formats} (as descrived in the @option{-J}
2834 option), it will issue a deprecation warning, and behave just like the
2835 @option{-J} option. New programs should not use this behaviour. If a
2836 directory happens to match a @var{format}, simple prefix it with @samp{./}
2837 to disable the backward compatibility.
2839 @item -D @var{target}
2840 @itemx --define @var{sym}[=@var{val}]
2841 Specify a @option{-D} option to pass to the preprocessor when reading an
2844 @item -U @var{target}
2845 @itemx --undefine @var{sym}
2846 Specify a @option{-U} option to pass to the preprocessor when reading an
2850 Ignored for compatibility with rc.
2853 Enable verbose mode. This tells you what the preprocessor is if you
2857 @item --language @var{val}
2858 Specify the default language to use when reading an @code{rc} file.
2859 @var{val} should be a hexadecimal language code. The low eight bits are
2860 the language, and the high eight bits are the sublanguage.
2862 @item --use-temp-file
2863 Use a temporary file to instead of using popen to read the output of
2864 the preprocessor. Use this option if the popen implementation is buggy
2865 on the host (eg., certain non-English language versions of Windows 95 and
2866 Windows 98 are known to have buggy popen where the output will instead
2869 @item --no-use-temp-file
2870 Use popen, not a temporary file, to read the output of the preprocessor.
2871 This is the default behaviour.
2875 Prints a usage summary.
2879 Prints the version number for @command{windres}.
2882 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2883 this will turn on parser debugging.
2889 @c man begin SEEALSO windres
2890 the Info entries for @file{binutils}.
2899 @command{dlltool} is used to create the files needed to create dynamic
2900 link libraries (DLLs) on systems which understand PE format image
2901 files such as Windows. A DLL contains an export table which contains
2902 information that the runtime loader needs to resolve references from a
2903 referencing program.
2905 The export table is generated by this program by reading in a
2906 @file{.def} file or scanning the @file{.a} and @file{.o} files which
2907 will be in the DLL. A @file{.o} file can contain information in
2908 special @samp{.drectve} sections with export information.
2911 @emph{Note:} @command{dlltool} is not always built as part of the
2912 binary utilities, since it is only useful for those targets which
2916 @c man title dlltool Create files needed to build and use DLLs.
2919 @c man begin SYNOPSIS dlltool
2920 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2921 [@option{-b}|@option{--base-file} @var{base-file-name}]
2922 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2923 [@option{-z}|@option{--output-def} @var{def-file-name}]
2924 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2925 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2926 [@option{--exclude-symbols} @var{list}]
2927 [@option{--no-default-excludes}]
2928 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2929 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2930 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2931 [@option{-A}|@option{--add-stdcall-alias}]
2932 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
2933 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2934 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
2935 [@option{-v}|@option{--verbose}]
2936 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2937 [object-file @dots{}]
2941 @c man begin DESCRIPTION dlltool
2943 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2944 @option{-b} options as well as object files specified on the command
2945 line. It then processes these inputs and if the @option{-e} option has
2946 been specified it creates a exports file. If the @option{-l} option
2947 has been specified it creates a library file and if the @option{-z} option
2948 has been specified it creates a def file. Any or all of the @option{-e},
2949 @option{-l} and @option{-z} options can be present in one invocation of
2952 When creating a DLL, along with the source for the DLL, it is necessary
2953 to have three other files. @command{dlltool} can help with the creation of
2956 The first file is a @file{.def} file which specifies which functions are
2957 exported from the DLL, which functions the DLL imports, and so on. This
2958 is a text file and can be created by hand, or @command{dlltool} can be used
2959 to create it using the @option{-z} option. In this case @command{dlltool}
2960 will scan the object files specified on its command line looking for
2961 those functions which have been specially marked as being exported and
2962 put entries for them in the @file{.def} file it creates.
2964 In order to mark a function as being exported from a DLL, it needs to
2965 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2966 section of the object file. This can be done in C by using the
2970 asm (".section .drectve");
2971 asm (".ascii \"-export:my_func\"");
2973 int my_func (void) @{ @dots{} @}
2976 The second file needed for DLL creation is an exports file. This file
2977 is linked with the object files that make up the body of the DLL and it
2978 handles the interface between the DLL and the outside world. This is a
2979 binary file and it can be created by giving the @option{-e} option to
2980 @command{dlltool} when it is creating or reading in a @file{.def} file.
2982 The third file needed for DLL creation is the library file that programs
2983 will link with in order to access the functions in the DLL. This file
2984 can be created by giving the @option{-l} option to dlltool when it
2985 is creating or reading in a @file{.def} file.
2987 @command{dlltool} builds the library file by hand, but it builds the
2988 exports file by creating temporary files containing assembler statements
2989 and then assembling these. The @option{-S} command line option can be
2990 used to specify the path to the assembler that dlltool will use,
2991 and the @option{-f} option can be used to pass specific flags to that
2992 assembler. The @option{-n} can be used to prevent dlltool from deleting
2993 these temporary assembler files when it is done, and if @option{-n} is
2994 specified twice then this will prevent dlltool from deleting the
2995 temporary object files it used to build the library.
2997 Here is an example of creating a DLL from a source file @samp{dll.c} and
2998 also creating a program (from an object file called @samp{program.o})
3003 dlltool -e exports.o -l dll.lib dll.o
3004 gcc dll.o exports.o -o dll.dll
3005 gcc program.o dll.lib -o program
3010 @c man begin OPTIONS dlltool
3012 The command line options have the following meanings:
3016 @item -d @var{filename}
3017 @itemx --input-def @var{filename}
3018 @cindex input .def file
3019 Specifies the name of a @file{.def} file to be read in and processed.
3021 @item -b @var{filename}
3022 @itemx --base-file @var{filename}
3024 Specifies the name of a base file to be read in and processed. The
3025 contents of this file will be added to the relocation section in the
3026 exports file generated by dlltool.
3028 @item -e @var{filename}
3029 @itemx --output-exp @var{filename}
3030 Specifies the name of the export file to be created by dlltool.
3032 @item -z @var{filename}
3033 @itemx --output-def @var{filename}
3034 Specifies the name of the @file{.def} file to be created by dlltool.
3036 @item -l @var{filename}
3037 @itemx --output-lib @var{filename}
3038 Specifies the name of the library file to be created by dlltool.
3040 @item --export-all-symbols
3041 Treat all global and weak defined symbols found in the input object
3042 files as symbols to be exported. There is a small list of symbols which
3043 are not exported by default; see the @option{--no-default-excludes}
3044 option. You may add to the list of symbols to not export by using the
3045 @option{--exclude-symbols} option.
3047 @item --no-export-all-symbols
3048 Only export symbols explicitly listed in an input @file{.def} file or in
3049 @samp{.drectve} sections in the input object files. This is the default
3050 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3051 attributes in the source code.
3053 @item --exclude-symbols @var{list}
3054 Do not export the symbols in @var{list}. This is a list of symbol names
3055 separated by comma or colon characters. The symbol names should not
3056 contain a leading underscore. This is only meaningful when
3057 @option{--export-all-symbols} is used.
3059 @item --no-default-excludes
3060 When @option{--export-all-symbols} is used, it will by default avoid
3061 exporting certain special symbols. The current list of symbols to avoid
3062 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3063 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3064 to go ahead and export these special symbols. This is only meaningful
3065 when @option{--export-all-symbols} is used.
3068 @itemx --as @var{path}
3069 Specifies the path, including the filename, of the assembler to be used
3070 to create the exports file.
3072 @item -f @var{options}
3073 @itemx --as-flags @var{options}
3074 Specifies any specific command line options to be passed to the
3075 assembler when building the exports file. This option will work even if
3076 the @option{-S} option is not used. This option only takes one argument,
3077 and if it occurs more than once on the command line, then later
3078 occurrences will override earlier occurrences. So if it is necessary to
3079 pass multiple options to the assembler they should be enclosed in
3083 @itemx --dll-name @var{name}
3084 Specifies the name to be stored in the @file{.def} file as the name of
3085 the DLL when the @option{-e} option is used. If this option is not
3086 present, then the filename given to the @option{-e} option will be
3087 used as the name of the DLL.
3089 @item -m @var{machine}
3090 @itemx -machine @var{machine}
3091 Specifies the type of machine for which the library file should be
3092 built. @command{dlltool} has a built in default type, depending upon how
3093 it was created, but this option can be used to override that. This is
3094 normally only useful when creating DLLs for an ARM processor, when the
3095 contents of the DLL are actually encode using Thumb instructions.
3098 @itemx --add-indirect
3099 Specifies that when @command{dlltool} is creating the exports file it
3100 should add a section which allows the exported functions to be
3101 referenced without using the import library. Whatever the hell that
3105 @itemx --add-underscore
3106 Specifies that when @command{dlltool} is creating the exports file it
3107 should prepend an underscore to the names of the exported functions.
3111 Specifies that when @command{dlltool} is creating the exports file it
3112 should not append the string @samp{@@ <number>}. These numbers are
3113 called ordinal numbers and they represent another way of accessing the
3114 function in a DLL, other than by name.
3117 @itemx --add-stdcall-alias
3118 Specifies that when @command{dlltool} is creating the exports file it
3119 should add aliases for stdcall symbols without @samp{@@ <number>}
3120 in addition to the symbols with @samp{@@ <number>}.
3123 @itemx --ext-prefix-alias @var{prefix}
3124 Causes @command{dlltool} to create external aliases for all DLL
3125 imports with the specified prefix. The aliases are created for both
3126 external and import symbols with no leading underscore.
3130 Specifies that when @command{dlltool} is creating the exports and library
3131 files it should omit the @code{.idata4} section. This is for compatibility
3132 with certain operating systems.
3136 Specifies that when @command{dlltool} is creating the exports and library
3137 files it should omit the @code{.idata5} section. This is for compatibility
3138 with certain operating systems.
3142 Specifies that @command{dlltool} should mark the objects in the library
3143 file and exports file that it produces as supporting interworking
3144 between ARM and Thumb code.
3148 Makes @command{dlltool} preserve the temporary assembler files it used to
3149 create the exports file. If this option is repeated then dlltool will
3150 also preserve the temporary object files it uses to create the library
3153 @item -t @var{prefix}
3154 @itemx --temp-prefix @var{prefix}
3155 Makes @command{dlltool} use @var{prefix} when constructing the names of
3156 temporary assembler and object files. By default, the temp file prefix
3157 is generated from the pid.
3161 Make dlltool describe what it is doing.
3165 Displays a list of command line options and then exits.
3169 Displays dlltool's version number and then exits.
3176 * def file format:: The format of the dlltool @file{.def} file
3179 @node def file format
3180 @section The format of the @command{dlltool} @file{.def} file
3182 A @file{.def} file contains any number of the following commands:
3186 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3187 The result is going to be named @var{name}@code{.exe}.
3189 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3190 The result is going to be named @var{name}@code{.dll}.
3192 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3193 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3194 Declares @var{name1} as an exported symbol from the DLL, with optional
3195 ordinal number @var{integer}, or declares @var{name1} as an alias
3196 (forward) of the function @var{external-name} in the DLL
3199 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) ) *}
3200 Declares that @var{external-name} or the exported function whose
3201 ordinal number is @var{integer} is to be imported from the file
3202 @var{module-name}. If @var{internal-name} is specified then this is
3203 the name that the imported function will be referred to in the body of
3206 @item @code{DESCRIPTION} @var{string}
3207 Puts @var{string} into the output @file{.exp} file in the
3208 @code{.rdata} section.
3210 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3211 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3212 Generates @code{--stack} or @code{--heap}
3213 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3214 section. The linker will see this and act upon it.
3216 @item @code{CODE} @var{attr} @code{+}
3217 @item @code{DATA} @var{attr} @code{+}
3218 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3219 Generates @code{--attr} @var{section-name} @var{attr} in the output
3220 @code{.drectve} section, where @var{attr} is one of @code{READ},
3221 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3222 this and act upon it.
3227 @c man begin SEEALSO dlltool
3228 The Info pages for @file{binutils}.
3235 @cindex ELF file information
3238 @c man title readelf Displays information about ELF files.
3241 @c man begin SYNOPSIS readelf
3242 readelf [@option{-a}|@option{--all}]
3243 [@option{-h}|@option{--file-header}]
3244 [@option{-l}|@option{--program-headers}|@option{--segments}]
3245 [@option{-S}|@option{--section-headers}|@option{--sections}]
3246 [@option{-g}|@option{--section-groups}]
3247 [@option{-N}|@option{--full-section-name}]
3248 [@option{-e}|@option{--headers}]
3249 [@option{-s}|@option{--syms}|@option{--symbols}]
3250 [@option{-n}|@option{--notes}]
3251 [@option{-r}|@option{--relocs}]
3252 [@option{-u}|@option{--unwind}]
3253 [@option{-d}|@option{--dynamic}]
3254 [@option{-V}|@option{--version-info}]
3255 [@option{-A}|@option{--arch-specific}]
3256 [@option{-D}|@option{--use-dynamic}]
3257 [@option{-x} <number>|@option{--hex-dump=}<number>]
3258 [@option{-w[liaprmfFsoR]}|
3259 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3260 [@option{-I}|@option{-histogram}]
3261 [@option{-v}|@option{--version}]
3262 [@option{-W}|@option{--wide}]
3263 [@option{-H}|@option{--help}]
3264 @var{elffile}@dots{}
3268 @c man begin DESCRIPTION readelf
3270 @command{readelf} displays information about one or more ELF format object
3271 files. The options control what particular information to display.
3273 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3274 64-bit ELF files are supported, as are archives containing ELF files.
3276 This program performs a similar function to @command{objdump} but it
3277 goes into more detail and it exists independently of the @sc{bfd}
3278 library, so if there is a bug in @sc{bfd} then readelf will not be
3283 @c man begin OPTIONS readelf
3285 The long and short forms of options, shown here as alternatives, are
3286 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3292 Equivalent to specifiying @option{--file-header},
3293 @option{--program-headers}, @option{--sections}, @option{--symbols},
3294 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3295 @option{--version-info}.
3298 @itemx --file-header
3299 @cindex ELF file header information
3300 Displays the information contained in the ELF header at the start of the
3304 @itemx --program-headers
3306 @cindex ELF program header information
3307 @cindex ELF segment information
3308 Displays the information contained in the file's segment headers, if it
3313 @itemx --section-headers
3314 @cindex ELF section information
3315 Displays the information contained in the file's section headers, if it
3319 @itemx --section-groups
3320 @cindex ELF section group information
3321 Displays the information contained in the file's section groups, if it
3325 @itemx --full-section-name
3326 @cindex ELF section name information
3327 Displays the full section name for @option{-S}.
3332 @cindex ELF symbol table information
3333 Displays the entries in symbol table section of the file, if it has one.
3337 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3342 Displays the contents of the NOTE segments and/or sections, if any.
3346 @cindex ELF reloc information
3347 Displays the contents of the file's relocation section, if it has one.
3351 @cindex unwind information
3352 Displays the contents of the file's unwind section, if it has one. Only
3353 the unwind sections for IA64 ELF files are currently supported.
3357 @cindex ELF dynamic section information
3358 Displays the contents of the file's dynamic section, if it has one.
3361 @itemx --version-info
3362 @cindex ELF version sections informations
3363 Displays the contents of the version sections in the file, it they
3367 @itemx --arch-specific
3368 Displays architecture-specific information in the file, if there
3372 @itemx --use-dynamic
3373 When displaying symbols, this option makes @command{readelf} use the
3374 symbol table in the file's dynamic section, rather than the one in the
3378 @itemx --hex-dump=<number>
3379 Displays the contents of the indicated section as a hexadecimal dump.
3381 @item -w[liaprmfFsoR]
3382 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3383 Displays the contents of the debug sections in the file, if any are
3384 present. If one of the optional letters or words follows the switch
3385 then only data found in those specific sections will be dumped.
3389 Display a histogram of bucket list lengths when displaying the contents
3390 of the symbol tables.
3394 Display the version number of readelf.
3398 Don't break output lines to fit into 80 columns. By default
3399 @command{readelf} breaks section header and segment listing lines for
3400 64-bit ELF files, so that they fit into 80 columns. This option causes
3401 @command{readelf} to print each section header resp. each segment one a
3402 single line, which is far more readable on terminals wider than 80 columns.
3406 Display the command line options understood by @command{readelf}.
3413 @c man begin SEEALSO readelf
3414 objdump(1), and the Info entries for @file{binutils}.
3418 @node Selecting The Target System
3419 @chapter Selecting the Target System
3421 You can specify two aspects of the target system to the @sc{gnu}
3422 binary file utilities, each in several ways:
3432 In the following summaries, the lists of ways to specify values are in
3433 order of decreasing precedence. The ways listed first override those
3436 The commands to list valid values only list the values for which the
3437 programs you are running were configured. If they were configured with
3438 @option{--enable-targets=all}, the commands list most of the available
3439 values, but a few are left out; not all targets can be configured in at
3440 once because some of them can only be configured @dfn{native} (on hosts
3441 with the same type as the target system).
3444 * Target Selection::
3445 * Architecture Selection::
3448 @node Target Selection
3449 @section Target Selection
3451 A @dfn{target} is an object file format. A given target may be
3452 supported for multiple architectures (@pxref{Architecture Selection}).
3453 A target selection may also have variations for different operating
3454 systems or architectures.
3456 The command to list valid target values is @samp{objdump -i}
3457 (the first column of output contains the relevant information).
3459 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3460 @samp{a.out-sunos-big}.
3462 You can also specify a target using a configuration triplet. This is
3463 the same sort of name that is passed to @file{configure} to specify a
3464 target. When you use a configuration triplet as an argument, it must be
3465 fully canonicalized. You can see the canonical version of a triplet by
3466 running the shell script @file{config.sub} which is included with the
3469 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3470 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3472 @subheading @command{objdump} Target
3478 command line option: @option{-b} or @option{--target}
3481 environment variable @code{GNUTARGET}
3484 deduced from the input file
3487 @subheading @command{objcopy} and @command{strip} Input Target
3493 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3496 environment variable @code{GNUTARGET}
3499 deduced from the input file
3502 @subheading @command{objcopy} and @command{strip} Output Target
3508 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3511 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3514 environment variable @code{GNUTARGET}
3517 deduced from the input file
3520 @subheading @command{nm}, @command{size}, and @command{strings} Target
3526 command line option: @option{--target}
3529 environment variable @code{GNUTARGET}
3532 deduced from the input file
3535 @node Architecture Selection
3536 @section Architecture Selection
3538 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3539 to run. Its name may contain a colon, separating the name of the
3540 processor family from the name of the particular @sc{cpu}.
3542 The command to list valid architecture values is @samp{objdump -i} (the
3543 second column contains the relevant information).
3545 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3547 @subheading @command{objdump} Architecture
3553 command line option: @option{-m} or @option{--architecture}
3556 deduced from the input file
3559 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3565 deduced from the input file
3568 @node Reporting Bugs
3569 @chapter Reporting Bugs
3571 @cindex reporting bugs
3573 Your bug reports play an essential role in making the binary utilities
3576 Reporting a bug may help you by bringing a solution to your problem, or
3577 it may not. But in any case the principal function of a bug report is
3578 to help the entire community by making the next version of the binary
3579 utilities work better. Bug reports are your contribution to their
3582 In order for a bug report to serve its purpose, you must include the
3583 information that enables us to fix the bug.
3586 * Bug Criteria:: Have you found a bug?
3587 * Bug Reporting:: How to report bugs
3591 @section Have You Found a Bug?
3592 @cindex bug criteria
3594 If you are not sure whether you have found a bug, here are some guidelines:
3597 @cindex fatal signal
3600 If a binary utility gets a fatal signal, for any input whatever, that is
3601 a bug. Reliable utilities never crash.
3603 @cindex error on valid input
3605 If a binary utility produces an error message for valid input, that is a
3609 If you are an experienced user of binary utilities, your suggestions for
3610 improvement are welcome in any case.
3614 @section How to Report Bugs
3616 @cindex bugs, reporting
3618 A number of companies and individuals offer support for @sc{gnu}
3619 products. If you obtained the binary utilities from a support
3620 organization, we recommend you contact that organization first.
3622 You can find contact information for many support companies and
3623 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3626 In any event, we also recommend that you send bug reports for the binary
3627 utilities to @samp{bug-binutils@@gnu.org}.
3629 The fundamental principle of reporting bugs usefully is this:
3630 @strong{report all the facts}. If you are not sure whether to state a
3631 fact or leave it out, state it!
3633 Often people omit facts because they think they know what causes the
3634 problem and assume that some details do not matter. Thus, you might
3635 assume that the name of a file you use in an example does not matter.
3636 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3637 a stray memory reference which happens to fetch from the location where
3638 that pathname is stored in memory; perhaps, if the pathname were
3639 different, the contents of that location would fool the utility into
3640 doing the right thing despite the bug. Play it safe and give a
3641 specific, complete example. That is the easiest thing for you to do,
3642 and the most helpful.
3644 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3645 it is new to us. Therefore, always write your bug reports on the assumption
3646 that the bug has not been reported previously.
3648 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3649 bell?'' This cannot help us fix a bug, so it is basically useless. We
3650 respond by asking for enough details to enable us to investigate.
3651 You might as well expedite matters by sending them to begin with.
3653 To enable us to fix the bug, you should include all these things:
3657 The version of the utility. Each utility announces it if you start it
3658 with the @option{--version} argument.
3660 Without this, we will not know whether there is any point in looking for
3661 the bug in the current version of the binary utilities.
3664 Any patches you may have applied to the source, including any patches
3665 made to the @code{BFD} library.
3668 The type of machine you are using, and the operating system name and
3672 What compiler (and its version) was used to compile the utilities---e.g.
3676 The command arguments you gave the utility to observe the bug. To
3677 guarantee you will not omit something important, list them all. A copy
3678 of the Makefile (or the output from make) is sufficient.
3680 If we were to try to guess the arguments, we would probably guess wrong
3681 and then we might not encounter the bug.
3684 A complete input file, or set of input files, that will reproduce the
3685 bug. If the utility is reading an object file or files, then it is
3686 generally most helpful to send the actual object files, uuencoded if
3687 necessary to get them through the mail system. Note that
3688 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3689 sending very large files to it. Making the files available for
3690 anonymous FTP is OK.
3692 If the source files were produced exclusively using @sc{gnu} programs
3693 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3694 may be OK to send the source files rather than the object files. In
3695 this case, be sure to say exactly what version of @command{gcc}, or
3696 whatever, was used to produce the object files. Also say how
3697 @command{gcc}, or whatever, was configured.
3700 A description of what behavior you observe that you believe is
3701 incorrect. For example, ``It gets a fatal signal.''
3703 Of course, if the bug is that the utility gets a fatal signal, then we
3704 will certainly notice it. But if the bug is incorrect output, we might
3705 not notice unless it is glaringly wrong. You might as well not give us
3706 a chance to make a mistake.
3708 Even if the problem you experience is a fatal signal, you should still
3709 say so explicitly. Suppose something strange is going on, such as your
3710 copy of the utility is out of synch, or you have encountered a bug in
3711 the C library on your system. (This has happened!) Your copy might
3712 crash and ours would not. If you told us to expect a crash, then when
3713 ours fails to crash, we would know that the bug was not happening for
3714 us. If you had not told us to expect a crash, then we would not be able
3715 to draw any conclusion from our observations.
3718 If you wish to suggest changes to the source, send us context diffs, as
3719 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3720 option. Always send diffs from the old file to the new file. If you
3721 wish to discuss something in the @command{ld} source, refer to it by
3722 context, not by line number.
3724 The line numbers in our development sources will not match those in your
3725 sources. Your line numbers would convey no useful information to us.
3728 Here are some things that are not necessary:
3732 A description of the envelope of the bug.
3734 Often people who encounter a bug spend a lot of time investigating
3735 which changes to the input file will make the bug go away and which
3736 changes will not affect it.
3738 This is often time consuming and not very useful, because the way we
3739 will find the bug is by running a single example under the debugger
3740 with breakpoints, not by pure deduction from a series of examples.
3741 We recommend that you save your time for something else.
3743 Of course, if you can find a simpler example to report @emph{instead}
3744 of the original one, that is a convenience for us. Errors in the
3745 output will be easier to spot, running under the debugger will take
3746 less time, and so on.
3748 However, simplification is not vital; if you do not want to do this,
3749 report the bug anyway and send us the entire test case you used.
3752 A patch for the bug.
3754 A patch for the bug does help us if it is a good one. But do not omit
3755 the necessary information, such as the test case, on the assumption that
3756 a patch is all we need. We might see problems with your patch and decide
3757 to fix the problem another way, or we might not understand it at all.
3759 Sometimes with programs as complicated as the binary utilities it is
3760 very hard to construct an example that will make the program follow a
3761 certain path through the code. If you do not send us the example, we
3762 will not be able to construct one, so we will not be able to verify that
3765 And if we cannot understand what bug you are trying to fix, or why your
3766 patch should be an improvement, we will not install it. A test case will
3767 help us to understand.
3770 A guess about what the bug is or what it depends on.
3772 Such guesses are usually wrong. Even we cannot guess right about such
3773 things without first using the debugger to find the facts.