1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004 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, 92, 93, 94, 95, 96, 97, 98, 99, 2000,
33 2001, 2002, 2003, 2004 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, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001,
58 @c 2002, 2003, 2004 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}
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, 92, 93, 94, 95, 96, 97, 1998, 2000, 2001,
84 2002, 2003, 2004 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. Uppercase indicates that a default value has been specified.
755 The symbol is a stabs symbol in an a.out object file. In this case, the
756 next values printed are the stabs other field, the stabs desc field, and
757 the stab type. Stabs symbols are used to hold debugging information.
759 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
760 ``stabs'' debug format}.
764 The symbol type is unknown, or object file format specific.
773 @c man begin OPTIONS nm
774 The long and short forms of options, shown here as alternatives, are
780 @itemx --print-file-name
781 @cindex input file name
783 @cindex source file name
784 Precede each symbol by the name of the input file (or archive member)
785 in which it was found, rather than identifying the input file once only,
786 before all of its symbols.
790 @cindex debugging symbols
791 Display all symbols, even debugger-only symbols; normally these are not
795 @cindex @command{nm} format
796 @cindex @command{nm} compatibility
797 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
800 @itemx --demangle[=@var{style}]
801 @cindex demangling in nm
802 Decode (@dfn{demangle}) low-level symbol names into user-level names.
803 Besides removing any initial underscore prepended by the system, this
804 makes C++ function names readable. Different compilers have different
805 mangling styles. The optional demangling style argument can be used to
806 choose an appropriate demangling style for your compiler. @xref{c++filt},
807 for more information on demangling.
810 Do not demangle low-level symbol names. This is the default.
814 @cindex dynamic symbols
815 Display the dynamic symbols rather than the normal symbols. This is
816 only meaningful for dynamic objects, such as certain types of shared
819 @item -f @var{format}
820 @itemx --format=@var{format}
821 @cindex @command{nm} format
822 @cindex @command{nm} compatibility
823 Use the output format @var{format}, which can be @code{bsd},
824 @code{sysv}, or @code{posix}. The default is @code{bsd}.
825 Only the first character of @var{format} is significant; it can be
826 either upper or lower case.
830 @cindex external symbols
831 Display only external symbols.
834 @itemx --line-numbers
835 @cindex symbol line numbers
836 For each symbol, use debugging information to try to find a filename and
837 line number. For a defined symbol, look for the line number of the
838 address of the symbol. For an undefined symbol, look for the line
839 number of a relocation entry which refers to the symbol. If line number
840 information can be found, print it after the other symbol information.
844 @itemx --numeric-sort
845 Sort symbols numerically by their addresses, rather than alphabetically
850 @cindex sorting symbols
851 Do not bother to sort the symbols in any order; print them in the order
856 Use the POSIX.2 standard output format instead of the default format.
857 Equivalent to @samp{-f posix}.
861 Print size, not the value, of defined symbols for the @code{bsd} output format.
865 @cindex symbol index, listing
866 When listing symbols from archive members, include the index: a mapping
867 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
868 contain definitions for which names.
871 @itemx --reverse-sort
872 Reverse the order of the sort (whether numeric or alphabetic); let the
876 Sort symbols by size. The size is computed as the difference between
877 the value of the symbol and the value of the symbol with the next higher
878 value. If the @code{bsd} output format is used the size of the symbol
879 is printed, rather than the value, and @samp{-S} must be used in order
880 both size and value to be printed.
883 Display symbols which have a target-specific special meaning. These
884 symbols are usually used by the target for some special processing and
885 are not normally helpful when included included in the normal symbol
886 lists. For example for ARM targets this option would skip the mapping
887 symbols used to mark transistions between ARM code, THUMB code and
891 @itemx --radix=@var{radix}
892 Use @var{radix} as the radix for printing the symbol values. It must be
893 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
895 @item --target=@var{bfdname}
896 @cindex object code format
897 Specify an object code format other than your system's default format.
898 @xref{Target Selection}, for more information.
901 @itemx --undefined-only
902 @cindex external symbols
903 @cindex undefined symbols
904 Display only undefined symbols (those external to each object file).
907 @cindex external symbols
908 @cindex undefined symbols
909 Display only defined symbols for each object file.
913 Show the version number of @command{nm} and exit.
916 This option is ignored for compatibility with the AIX version of
917 @command{nm}. It takes one parameter which must be the string
918 @option{32_64}. The default mode of AIX @command{nm} corresponds
919 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
922 Show a summary of the options to @command{nm} and exit.
928 @c man begin SEEALSO nm
929 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
936 @c man title objcopy copy and translate object files
939 @c man begin SYNOPSIS objcopy
940 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
941 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
942 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
943 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
944 [@option{-S}|@option{--strip-all}]
945 [@option{-g}|@option{--strip-debug}]
946 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
947 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
948 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
949 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
950 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
951 [@option{-w}|@option{--wildcard}]
952 [@option{-x}|@option{--discard-all}]
953 [@option{-X}|@option{--discard-locals}]
954 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
955 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
956 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
957 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
958 [@option{-p}|@option{--preserve-dates}]
959 [@option{--debugging}]
960 [@option{--gap-fill=}@var{val}]
961 [@option{--pad-to=}@var{address}]
962 [@option{--set-start=}@var{val}]
963 [@option{--adjust-start=}@var{incr}]
964 [@option{--change-addresses=}@var{incr}]
965 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
966 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
967 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
968 [@option{--change-warnings}] [@option{--no-change-warnings}]
969 [@option{--set-section-flags} @var{section}=@var{flags}]
970 [@option{--add-section} @var{sectionname}=@var{filename}]
971 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
972 [@option{--change-leading-char}] [@option{--remove-leading-char}]
973 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
974 [@option{--redefine-sym} @var{old}=@var{new}]
975 [@option{--redefine-syms=}@var{filename}]
977 [@option{--keep-symbols=}@var{filename}]
978 [@option{--strip-symbols=}@var{filename}]
979 [@option{--keep-global-symbols=}@var{filename}]
980 [@option{--localize-symbols=}@var{filename}]
981 [@option{--weaken-symbols=}@var{filename}]
982 [@option{--alt-machine-code=}@var{index}]
983 [@option{--prefix-symbols=}@var{string}]
984 [@option{--prefix-sections=}@var{string}]
985 [@option{--prefix-alloc-sections=}@var{string}]
986 [@option{--add-gnu-debuglink=}@var{path-to-file}]
987 [@option{--only-keep-debug}]
988 [@option{--writable-text}]
989 [@option{--readonly-text}]
992 [@option{-v}|@option{--verbose}]
993 [@option{-V}|@option{--version}]
994 [@option{--help}] [@option{--info}]
995 @var{infile} [@var{outfile}]
999 @c man begin DESCRIPTION objcopy
1000 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1001 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1002 read and write the object files. It can write the destination object
1003 file in a format different from that of the source object file. The
1004 exact behavior of @command{objcopy} is controlled by command-line options.
1005 Note that @command{objcopy} should be able to copy a fully linked file
1006 between any two formats. However, copying a relocatable object file
1007 between any two formats may not work as expected.
1009 @command{objcopy} creates temporary files to do its translations and
1010 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1011 translation work; it has access to all the formats described in @sc{bfd}
1012 and thus is able to recognize most formats without being told
1013 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1015 @command{objcopy} can be used to generate S-records by using an output
1016 target of @samp{srec} (e.g., use @samp{-O srec}).
1018 @command{objcopy} can be used to generate a raw binary file by using an
1019 output target of @samp{binary} (e.g., use @option{-O binary}). When
1020 @command{objcopy} generates a raw binary file, it will essentially produce
1021 a memory dump of the contents of the input object file. All symbols and
1022 relocation information will be discarded. The memory dump will start at
1023 the load address of the lowest section copied into the output file.
1025 When generating an S-record or a raw binary file, it may be helpful to
1026 use @option{-S} to remove sections containing debugging information. In
1027 some cases @option{-R} will be useful to remove sections which contain
1028 information that is not needed by the binary file.
1030 Note---@command{objcopy} is not able to change the endianness of its input
1031 files. If the input format has an endianness (some formats do not),
1032 @command{objcopy} can only copy the inputs into file formats that have the
1033 same endianness or which have no endianness (e.g., @samp{srec}).
1037 @c man begin OPTIONS objcopy
1041 @itemx @var{outfile}
1042 The input and output files, respectively.
1043 If you do not specify @var{outfile}, @command{objcopy} creates a
1044 temporary file and destructively renames the result with
1045 the name of @var{infile}.
1047 @item -I @var{bfdname}
1048 @itemx --input-target=@var{bfdname}
1049 Consider the source file's object format to be @var{bfdname}, rather than
1050 attempting to deduce it. @xref{Target Selection}, for more information.
1052 @item -O @var{bfdname}
1053 @itemx --output-target=@var{bfdname}
1054 Write the output file using the object format @var{bfdname}.
1055 @xref{Target Selection}, for more information.
1057 @item -F @var{bfdname}
1058 @itemx --target=@var{bfdname}
1059 Use @var{bfdname} as the object format for both the input and the output
1060 file; i.e., simply transfer data from source to destination with no
1061 translation. @xref{Target Selection}, for more information.
1063 @item -B @var{bfdarch}
1064 @itemx --binary-architecture=@var{bfdarch}
1065 Useful when transforming a raw binary input file into an object file.
1066 In this case the output architecture can be set to @var{bfdarch}. This
1067 option will be ignored if the input file has a known @var{bfdarch}. You
1068 can access this binary data inside a program by referencing the special
1069 symbols that are created by the conversion process. These symbols are
1070 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1071 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1072 an object file and then access it in your code using these symbols.
1074 @item -j @var{sectionname}
1075 @itemx --only-section=@var{sectionname}
1076 Copy only the named section from the input file to the output file.
1077 This option may be given more than once. Note that using this option
1078 inappropriately may make the output file unusable.
1080 @item -R @var{sectionname}
1081 @itemx --remove-section=@var{sectionname}
1082 Remove any section named @var{sectionname} from the output file. This
1083 option may be given more than once. Note that using this option
1084 inappropriately may make the output file unusable.
1088 Do not copy relocation and symbol information from the source file.
1091 @itemx --strip-debug
1092 Do not copy debugging symbols or sections from the source file.
1094 @item --strip-unneeded
1095 Strip all symbols that are not needed for relocation processing.
1097 @item -K @var{symbolname}
1098 @itemx --keep-symbol=@var{symbolname}
1099 Copy only symbol @var{symbolname} from the source file. This option may
1100 be given more than once.
1102 @item -N @var{symbolname}
1103 @itemx --strip-symbol=@var{symbolname}
1104 Do not copy symbol @var{symbolname} from the source file. This option
1105 may be given more than once.
1107 @item -G @var{symbolname}
1108 @itemx --keep-global-symbol=@var{symbolname}
1109 Keep only symbol @var{symbolname} global. Make all other symbols local
1110 to the file, so that they are not visible externally. This option may
1111 be given more than once.
1113 @item -L @var{symbolname}
1114 @itemx --localize-symbol=@var{symbolname}
1115 Make symbol @var{symbolname} local to the file, so that it is not
1116 visible externally. This option may be given more than once.
1118 @item -W @var{symbolname}
1119 @itemx --weaken-symbol=@var{symbolname}
1120 Make symbol @var{symbolname} weak. This option may be given more than once.
1124 Permit regular expressions in @var{symbolname}s used in other command
1125 line options. The question mark (?), asterisk (*), backslash (\) and
1126 square brackets ([]) operators can be used anywhere in the symbol
1127 name. If the first character of the symbol name is the exclamation
1128 point (!) then the sense of the switch is reversed for that symbol.
1135 would cause objcopy to weaken all symbols that start with ``fo''
1136 except for the symbol ``foo''.
1139 @itemx --discard-all
1140 Do not copy non-global symbols from the source file.
1141 @c FIXME any reason to prefer "non-global" to "local" here?
1144 @itemx --discard-locals
1145 Do not copy compiler-generated local symbols.
1146 (These usually start with @samp{L} or @samp{.}.)
1149 @itemx --byte=@var{byte}
1150 Keep only every @var{byte}th byte of the input file (header data is not
1151 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1152 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1153 option, or the default of 4. This option is useful for creating files
1154 to program @sc{rom}. It is typically used with an @code{srec} output
1157 @item -i @var{interleave}
1158 @itemx --interleave=@var{interleave}
1159 Only copy one out of every @var{interleave} bytes. Select which byte to
1160 copy with the @option{-b} or @option{--byte} option. The default is 4.
1161 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1165 @itemx --preserve-dates
1166 Set the access and modification dates of the output file to be the same
1167 as those of the input file.
1170 Convert debugging information, if possible. This is not the default
1171 because only certain debugging formats are supported, and the
1172 conversion process can be time consuming.
1174 @item --gap-fill @var{val}
1175 Fill gaps between sections with @var{val}. This operation applies to
1176 the @emph{load address} (LMA) of the sections. It is done by increasing
1177 the size of the section with the lower address, and filling in the extra
1178 space created with @var{val}.
1180 @item --pad-to @var{address}
1181 Pad the output file up to the load address @var{address}. This is
1182 done by increasing the size of the last section. The extra space is
1183 filled in with the value specified by @option{--gap-fill} (default zero).
1185 @item --set-start @var{val}
1186 Set the start address of the new file to @var{val}. Not all object file
1187 formats support setting the start address.
1189 @item --change-start @var{incr}
1190 @itemx --adjust-start @var{incr}
1191 @cindex changing start address
1192 Change the start address by adding @var{incr}. Not all object file
1193 formats support setting the start address.
1195 @item --change-addresses @var{incr}
1196 @itemx --adjust-vma @var{incr}
1197 @cindex changing object addresses
1198 Change the VMA and LMA addresses of all sections, as well as the start
1199 address, by adding @var{incr}. Some object file formats do not permit
1200 section addresses to be changed arbitrarily. Note that this does not
1201 relocate the sections; if the program expects sections to be loaded at a
1202 certain address, and this option is used to change the sections such
1203 that they are loaded at a different address, the program may fail.
1205 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1206 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1207 @cindex changing section address
1208 Set or change both the VMA address and the LMA address of the named
1209 @var{section}. If @samp{=} is used, the section address is set to
1210 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1211 section address. See the comments under @option{--change-addresses},
1212 above. If @var{section} does not exist in the input file, a warning will
1213 be issued, unless @option{--no-change-warnings} is used.
1215 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1216 @cindex changing section LMA
1217 Set or change the LMA address of the named @var{section}. The LMA
1218 address is the address where the section will be loaded into memory at
1219 program load time. Normally this is the same as the VMA address, which
1220 is the address of the section at program run time, but on some systems,
1221 especially those where a program is held in ROM, the two can be
1222 different. If @samp{=} is used, the section address is set to
1223 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1224 section address. See the comments under @option{--change-addresses},
1225 above. If @var{section} does not exist in the input file, a warning
1226 will be issued, unless @option{--no-change-warnings} is used.
1228 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1229 @cindex changing section VMA
1230 Set or change the VMA address of the named @var{section}. The VMA
1231 address is the address where the section will be located once the
1232 program has started executing. Normally this is the same as the LMA
1233 address, which is the address where the section will be loaded into
1234 memory, but on some systems, especially those where a program is held in
1235 ROM, the two can be different. If @samp{=} is used, the section address
1236 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1237 from the section address. See the comments under
1238 @option{--change-addresses}, above. If @var{section} does not exist in
1239 the input file, a warning will be issued, unless
1240 @option{--no-change-warnings} is used.
1242 @item --change-warnings
1243 @itemx --adjust-warnings
1244 If @option{--change-section-address} or @option{--change-section-lma} or
1245 @option{--change-section-vma} is used, and the named section does not
1246 exist, issue a warning. This is the default.
1248 @item --no-change-warnings
1249 @itemx --no-adjust-warnings
1250 Do not issue a warning if @option{--change-section-address} or
1251 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1252 if the named section does not exist.
1254 @item --set-section-flags @var{section}=@var{flags}
1255 Set the flags for the named section. The @var{flags} argument is a
1256 comma separated string of flag names. The recognized names are
1257 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1258 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1259 @samp{debug}. You can set the @samp{contents} flag for a section which
1260 does not have contents, but it is not meaningful to clear the
1261 @samp{contents} flag of a section which does have contents--just remove
1262 the section instead. Not all flags are meaningful for all object file
1265 @item --add-section @var{sectionname}=@var{filename}
1266 Add a new section named @var{sectionname} while copying the file. The
1267 contents of the new section are taken from the file @var{filename}. The
1268 size of the section will be the size of the file. This option only
1269 works on file formats which can support sections with arbitrary names.
1271 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1272 Rename a section from @var{oldname} to @var{newname}, optionally
1273 changing the section's flags to @var{flags} in the process. This has
1274 the advantage over usng a linker script to perform the rename in that
1275 the output stays as an object file and does not become a linked
1278 This option is particularly helpful when the input format is binary,
1279 since this will always create a section called .data. If for example,
1280 you wanted instead to create a section called .rodata containing binary
1281 data you could use the following command line to achieve it:
1284 objcopy -I binary -O <output_format> -B <architecture> \
1285 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1286 <input_binary_file> <output_object_file>
1289 @item --change-leading-char
1290 Some object file formats use special characters at the start of
1291 symbols. The most common such character is underscore, which compilers
1292 often add before every symbol. This option tells @command{objcopy} to
1293 change the leading character of every symbol when it converts between
1294 object file formats. If the object file formats use the same leading
1295 character, this option has no effect. Otherwise, it will add a
1296 character, or remove a character, or change a character, as
1299 @item --remove-leading-char
1300 If the first character of a global symbol is a special symbol leading
1301 character used by the object file format, remove the character. The
1302 most common symbol leading character is underscore. This option will
1303 remove a leading underscore from all global symbols. This can be useful
1304 if you want to link together objects of different file formats with
1305 different conventions for symbol names. This is different from
1306 @option{--change-leading-char} because it always changes the symbol name
1307 when appropriate, regardless of the object file format of the output
1310 @item --srec-len=@var{ival}
1311 Meaningful only for srec output. Set the maximum length of the Srecords
1312 being produced to @var{ival}. This length covers both address, data and
1315 @item --srec-forceS3
1316 Meaningful only for srec output. Avoid generation of S1/S2 records,
1317 creating S3-only record format.
1319 @item --redefine-sym @var{old}=@var{new}
1320 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1321 when one is trying link two things together for which you have no
1322 source, and there are name collisions.
1324 @item --redefine-syms=@var{filename}
1325 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1326 listed in the file @var{filename}. @var{filename} is simply a flat file,
1327 with one symbol pair per line. Line comments may be introduced by the hash
1328 character. This option may be given more than once.
1331 Change all global symbols in the file to be weak. This can be useful
1332 when building an object which will be linked against other objects using
1333 the @option{-R} option to the linker. This option is only effective when
1334 using an object file format which supports weak symbols.
1336 @item --keep-symbols=@var{filename}
1337 Apply @option{--keep-symbol} option to each symbol listed in the file
1338 @var{filename}. @var{filename} is simply a flat file, with one symbol
1339 name per line. Line comments may be introduced by the hash character.
1340 This option may be given more than once.
1342 @item --strip-symbols=@var{filename}
1343 Apply @option{--strip-symbol} option to each symbol listed in the file
1344 @var{filename}. @var{filename} is simply a flat file, with one symbol
1345 name per line. Line comments may be introduced by the hash character.
1346 This option may be given more than once.
1348 @item --keep-global-symbols=@var{filename}
1349 Apply @option{--keep-global-symbol} option to each symbol listed in the
1350 file @var{filename}. @var{filename} is simply a flat file, with one
1351 symbol name per line. Line comments may be introduced by the hash
1352 character. This option may be given more than once.
1354 @item --localize-symbols=@var{filename}
1355 Apply @option{--localize-symbol} option to each symbol listed in the file
1356 @var{filename}. @var{filename} is simply a flat file, with one symbol
1357 name per line. Line comments may be introduced by the hash character.
1358 This option may be given more than once.
1360 @item --weaken-symbols=@var{filename}
1361 Apply @option{--weaken-symbol} option to each symbol listed in the file
1362 @var{filename}. @var{filename} is simply a flat file, with one symbol
1363 name per line. Line comments may be introduced by the hash character.
1364 This option may be given more than once.
1366 @item --alt-machine-code=@var{index}
1367 If the output architecture has alternate machine codes, use the
1368 @var{index}th code instead of the default one. This is useful in case
1369 a machine is assigned an official code and the tool-chain adopts the
1370 new code, but other applications still depend on the original code
1373 @item --writable-text
1374 Mark the output text as writable. This option isn't meaningful for all
1375 object file formats.
1377 @item --readonly-text
1378 Make the output text write protected. This option isn't meaningful for all
1379 object file formats.
1382 Mark the output file as demand paged. This option isn't meaningful for all
1383 object file formats.
1386 Mark the output file as impure. This option isn't meaningful for all
1387 object file formats.
1389 @item --prefix-symbols=@var{string}
1390 Prefix all symbols in the output file with @var{string}.
1392 @item --prefix-sections=@var{string}
1393 Prefix all section names in the output file with @var{string}.
1395 @item --prefix-alloc-sections=@var{string}
1396 Prefix all the names of all allocated sections in the output file with
1399 @item --add-gnu-debuglink=@var{path-to-file}
1400 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1401 and adds it to the output file.
1403 @item --only-keep-debug
1404 Strip a file, removing any sections that would be stripped by
1405 @option{--strip-debug} and leaving the debugging sections.
1407 The intention is that this option will be used in conjunction with
1408 @option{--add-gnu-debuglink} to create a two part executable. One a
1409 stripped binary which will occupy less space in RAM and in a
1410 distribution and the second a debugging information file which is only
1411 needed if debugging abilities are required. The suggested procedure
1412 to create these files is as follows:
1415 @item Link the executable as normal. Assuming that is is called
1417 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1418 create a file containing the debugging info.
1419 @item Run @code{objcopy --strip-debug foo} to create a
1420 stripped executable.
1421 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1422 to add a link to the debugging info into the stripped executable.
1425 Note - the choice of @code{.dbg} as an extension for the debug info
1426 file is arbitrary. Also the @code{--only-keep-debug} step is
1427 optional. You could instead do this:
1430 @item Link the executable as normal.
1431 @item Copy @code{foo} to @code{foo.full}
1432 @item Run @code{objcopy --strip-debug foo}
1433 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1436 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
1437 full executable. It does not have to be a file created by the
1438 @option{--only-keep-debug} switch.
1442 Show the version number of @command{objcopy}.
1446 Verbose output: list all object files modified. In the case of
1447 archives, @samp{objcopy -V} lists all members of the archive.
1450 Show a summary of the options to @command{objcopy}.
1453 Display a list showing all architectures and object formats available.
1459 @c man begin SEEALSO objcopy
1460 ld(1), objdump(1), and the Info entries for @file{binutils}.
1467 @cindex object file information
1470 @c man title objdump display information from object files.
1473 @c man begin SYNOPSIS objdump
1474 objdump [@option{-a}|@option{--archive-headers}]
1475 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1476 [@option{-C}|@option{--demangle}[=@var{style}] ]
1477 [@option{-d}|@option{--disassemble}]
1478 [@option{-D}|@option{--disassemble-all}]
1479 [@option{-z}|@option{--disassemble-zeroes}]
1480 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1481 [@option{-f}|@option{--file-headers}]
1482 [@option{--file-start-context}]
1483 [@option{-g}|@option{--debugging}]
1484 [@option{-e}|@option{--debugging-tags}]
1485 [@option{-h}|@option{--section-headers}|@option{--headers}]
1486 [@option{-i}|@option{--info}]
1487 [@option{-j} @var{section}|@option{--section=}@var{section}]
1488 [@option{-l}|@option{--line-numbers}]
1489 [@option{-S}|@option{--source}]
1490 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1491 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1492 [@option{-p}|@option{--private-headers}]
1493 [@option{-r}|@option{--reloc}]
1494 [@option{-R}|@option{--dynamic-reloc}]
1495 [@option{-s}|@option{--full-contents}]
1496 [@option{-G}|@option{--stabs}]
1497 [@option{-t}|@option{--syms}]
1498 [@option{-T}|@option{--dynamic-syms}]
1499 [@option{-x}|@option{--all-headers}]
1500 [@option{-w}|@option{--wide}]
1501 [@option{--start-address=}@var{address}]
1502 [@option{--stop-address=}@var{address}]
1503 [@option{--prefix-addresses}]
1504 [@option{--[no-]show-raw-insn}]
1505 [@option{--adjust-vma=}@var{offset}]
1506 [@option{--special-syms}]
1507 [@option{-V}|@option{--version}]
1508 [@option{-H}|@option{--help}]
1509 @var{objfile}@dots{}
1513 @c man begin DESCRIPTION objdump
1515 @command{objdump} displays information about one or more object files.
1516 The options control what particular information to display. This
1517 information is mostly useful to programmers who are working on the
1518 compilation tools, as opposed to programmers who just want their
1519 program to compile and work.
1521 @var{objfile}@dots{} are the object files to be examined. When you
1522 specify archives, @command{objdump} shows information on each of the member
1527 @c man begin OPTIONS objdump
1529 The long and short forms of options, shown here as alternatives, are
1530 equivalent. At least one option from the list
1531 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1535 @itemx --archive-header
1536 @cindex archive headers
1537 If any of the @var{objfile} files are archives, display the archive
1538 header information (in a format similar to @samp{ls -l}). Besides the
1539 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1540 the object file format of each archive member.
1542 @item --adjust-vma=@var{offset}
1543 @cindex section addresses in objdump
1544 @cindex VMA in objdump
1545 When dumping information, first add @var{offset} to all the section
1546 addresses. This is useful if the section addresses do not correspond to
1547 the symbol table, which can happen when putting sections at particular
1548 addresses when using a format which can not represent section addresses,
1551 @item -b @var{bfdname}
1552 @itemx --target=@var{bfdname}
1553 @cindex object code format
1554 Specify that the object-code format for the object files is
1555 @var{bfdname}. This option may not be necessary; @var{objdump} can
1556 automatically recognize many formats.
1560 objdump -b oasys -m vax -h fu.o
1563 displays summary information from the section headers (@option{-h}) of
1564 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1565 file in the format produced by Oasys compilers. You can list the
1566 formats available with the @option{-i} option.
1567 @xref{Target Selection}, for more information.
1570 @itemx --demangle[=@var{style}]
1571 @cindex demangling in objdump
1572 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1573 Besides removing any initial underscore prepended by the system, this
1574 makes C++ function names readable. Different compilers have different
1575 mangling styles. The optional demangling style argument can be used to
1576 choose an appropriate demangling style for your compiler. @xref{c++filt},
1577 for more information on demangling.
1581 Display debugging information. This attempts to parse debugging
1582 information stored in the file and print it out using a C like syntax.
1583 Only certain types of debugging information have been implemented.
1584 Some other types are supported by @command{readelf -w}.
1588 @itemx --debugging-tags
1589 Like @option{-g}, but the information is generated in a format compatible
1593 @itemx --disassemble
1594 @cindex disassembling object code
1595 @cindex machine instructions
1596 Display the assembler mnemonics for the machine instructions from
1597 @var{objfile}. This option only disassembles those sections which are
1598 expected to contain instructions.
1601 @itemx --disassemble-all
1602 Like @option{-d}, but disassemble the contents of all sections, not just
1603 those expected to contain instructions.
1605 @item --prefix-addresses
1606 When disassembling, print the complete address on each line. This is
1607 the older disassembly format.
1611 @itemx --endian=@{big|little@}
1613 @cindex disassembly endianness
1614 Specify the endianness of the object files. This only affects
1615 disassembly. This can be useful when disassembling a file format which
1616 does not describe endianness information, such as S-records.
1619 @itemx --file-headers
1620 @cindex object file header
1621 Display summary information from the overall header of
1622 each of the @var{objfile} files.
1624 @item --file-start-context
1625 @cindex source code context
1626 Specify that when displaying interlisted source code/disassembly
1627 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1628 context to the start of the file.
1631 @itemx --section-headers
1633 @cindex section headers
1634 Display summary information from the section headers of the
1637 File segments may be relocated to nonstandard addresses, for example by
1638 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1639 @command{ld}. However, some object file formats, such as a.out, do not
1640 store the starting address of the file segments. In those situations,
1641 although @command{ld} relocates the sections correctly, using @samp{objdump
1642 -h} to list the file section headers cannot show the correct addresses.
1643 Instead, it shows the usual addresses, which are implicit for the
1648 Print a summary of the options to @command{objdump} and exit.
1652 @cindex architectures available
1653 @cindex object formats available
1654 Display a list showing all architectures and object formats available
1655 for specification with @option{-b} or @option{-m}.
1658 @itemx --section=@var{name}
1659 @cindex section information
1660 Display information only for section @var{name}.
1663 @itemx --line-numbers
1664 @cindex source filenames for object files
1665 Label the display (using debugging information) with the filename and
1666 source line numbers corresponding to the object code or relocs shown.
1667 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1669 @item -m @var{machine}
1670 @itemx --architecture=@var{machine}
1671 @cindex architecture
1672 @cindex disassembly architecture
1673 Specify the architecture to use when disassembling object files. This
1674 can be useful when disassembling object files which do not describe
1675 architecture information, such as S-records. You can list the available
1676 architectures with the @option{-i} option.
1678 @item -M @var{options}
1679 @itemx --disassembler-options=@var{options}
1680 Pass target specific information to the disassembler. Only supported on
1681 some targets. If it is necessary to specify more than one
1682 disassembler option then multiple @option{-M} options can be used or
1683 can be placed together into a comma separated list.
1685 If the target is an ARM architecture then this switch can be used to
1686 select which register name set is used during disassembler. Specifying
1687 @option{-M reg-name-std} (the default) will select the register names as
1688 used in ARM's instruction set documentation, but with register 13 called
1689 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1690 @option{-M reg-names-apcs} will select the name set used by the ARM
1691 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1692 just use @samp{r} followed by the register number.
1694 There are also two variants on the APCS register naming scheme enabled
1695 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1696 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1697 with the normal register names or the special register names).
1699 This option can also be used for ARM architectures to force the
1700 disassembler to interpret all instructions as Thumb instructions by
1701 using the switch @option{--disassembler-options=force-thumb}. This can be
1702 useful when attempting to disassemble thumb code produced by other
1705 For the x86, some of the options duplicate functions of the @option{-m}
1706 switch, but allow finer grained control. Multiple selections from the
1707 following may be specified as a comma separated string.
1708 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1709 the given architecture. @option{intel} and @option{att} select between
1710 intel syntax mode and AT&T syntax mode. @option{addr32},
1711 @option{addr16}, @option{data32} and @option{data16} specify the default
1712 address size and operand size. These four options will be overridden if
1713 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1714 option string. Lastly, @option{suffix}, when in AT&T mode,
1715 instructs the disassembler to print a mnemonic suffix even when the
1716 suffix could be inferred by the operands.
1718 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1719 disassembly of BookE instructions. @option{32} and @option{64} select
1720 PowerPC and PowerPC64 disassembly, respectively.
1722 For MIPS, this option controls the printing of register names in
1723 disassembled instructions. Multiple selections from the
1724 following may be specified as a comma separated string, and invalid
1725 options are ignored:
1728 @item gpr-names=@var{ABI}
1729 Print GPR (general-purpose register) names as appropriate
1730 for the specified ABI. By default, GPR names are selected according to
1731 the ABI of the binary being disassembled.
1733 @item fpr-names=@var{ABI}
1734 Print FPR (floating-point register) names as
1735 appropriate for the specified ABI. By default, FPR numbers are printed
1738 @item cp0-names=@var{ARCH}
1739 Print CP0 (system control coprocessor; coprocessor 0) register names
1740 as appropriate for the CPU or architecture specified by
1741 @var{ARCH}. By default, CP0 register names are selected according to
1742 the architecture and CPU of the binary being disassembled.
1744 @item hwr-names=@var{ARCH}
1745 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1746 as appropriate for the CPU or architecture specified by
1747 @var{ARCH}. By default, HWR names are selected according to
1748 the architecture and CPU of the binary being disassembled.
1750 @item reg-names=@var{ABI}
1751 Print GPR and FPR names as appropriate for the selected ABI.
1753 @item reg-names=@var{ARCH}
1754 Print CPU-specific register names (CP0 register and HWR names)
1755 as appropriate for the selected CPU or architecture.
1758 For any of the options listed above, @var{ABI} or
1759 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1760 rather than names, for the selected types of registers.
1761 You can list the available values of @var{ABI} and @var{ARCH} using
1762 the @option{--help} option.
1765 @itemx --private-headers
1766 Print information that is specific to the object file format. The exact
1767 information printed depends upon the object file format. For some
1768 object file formats, no additional information is printed.
1772 @cindex relocation entries, in object file
1773 Print the relocation entries of the file. If used with @option{-d} or
1774 @option{-D}, the relocations are printed interspersed with the
1778 @itemx --dynamic-reloc
1779 @cindex dynamic relocation entries, in object file
1780 Print the dynamic relocation entries of the file. This is only
1781 meaningful for dynamic objects, such as certain types of shared
1785 @itemx --full-contents
1786 @cindex sections, full contents
1787 @cindex object file sections
1788 Display the full contents of any sections requested. By default all
1789 non-empty sections are displayed.
1793 @cindex source disassembly
1794 @cindex disassembly, with source
1795 Display source code intermixed with disassembly, if possible. Implies
1798 @item --show-raw-insn
1799 When disassembling instructions, print the instruction in hex as well as
1800 in symbolic form. This is the default except when
1801 @option{--prefix-addresses} is used.
1803 @item --no-show-raw-insn
1804 When disassembling instructions, do not print the instruction bytes.
1805 This is the default when @option{--prefix-addresses} is used.
1811 @cindex debug symbols
1812 @cindex ELF object file format
1813 Display the full contents of any sections requested. Display the
1814 contents of the .stab and .stab.index and .stab.excl sections from an
1815 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1816 @code{.stab} debugging symbol-table entries are carried in an ELF
1817 section. In most other file formats, debugging symbol-table entries are
1818 interleaved with linkage symbols, and are visible in the @option{--syms}
1821 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1822 Overview,stabs.info, The ``stabs'' debug format}.
1825 @item --start-address=@var{address}
1826 @cindex start-address
1827 Start displaying data at the specified address. This affects the output
1828 of the @option{-d}, @option{-r} and @option{-s} options.
1830 @item --stop-address=@var{address}
1831 @cindex stop-address
1832 Stop displaying data at the specified address. This affects the output
1833 of the @option{-d}, @option{-r} and @option{-s} options.
1837 @cindex symbol table entries, printing
1838 Print the symbol table entries of the file.
1839 This is similar to the information provided by the @samp{nm} program.
1842 @itemx --dynamic-syms
1843 @cindex dynamic symbol table entries, printing
1844 Print the dynamic symbol table entries of the file. This is only
1845 meaningful for dynamic objects, such as certain types of shared
1846 libraries. This is similar to the information provided by the @samp{nm}
1847 program when given the @option{-D} (@option{--dynamic}) option.
1849 @item --special-syms
1850 When displaying symbols include those which the target considers to be
1851 special in some way and which would not normally be of interest to the
1856 Print the version number of @command{objdump} and exit.
1859 @itemx --all-headers
1860 @cindex all header information, object file
1861 @cindex header information, all
1862 Display all available header information, including the symbol table and
1863 relocation entries. Using @option{-x} is equivalent to specifying all of
1864 @option{-a -f -h -p -r -t}.
1868 @cindex wide output, printing
1869 Format some lines for output devices that have more than 80 columns.
1870 Also do not truncate symbol names when they are displayed.
1873 @itemx --disassemble-zeroes
1874 Normally the disassembly output will skip blocks of zeroes. This
1875 option directs the disassembler to disassemble those blocks, just like
1882 @c man begin SEEALSO objdump
1883 nm(1), readelf(1), and the Info entries for @file{binutils}.
1891 @cindex archive contents
1892 @cindex symbol index
1894 @c man title ranlib generate index to archive.
1897 @c man begin SYNOPSIS ranlib
1898 ranlib [@option{-vV}] @var{archive}
1902 @c man begin DESCRIPTION ranlib
1904 @command{ranlib} generates an index to the contents of an archive and
1905 stores it in the archive. The index lists each symbol defined by a
1906 member of an archive that is a relocatable object file.
1908 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1910 An archive with such an index speeds up linking to the library and
1911 allows routines in the library to call each other without regard to
1912 their placement in the archive.
1914 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1915 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1920 @c man begin OPTIONS ranlib
1926 Show the version number of @command{ranlib}.
1932 @c man begin SEEALSO ranlib
1933 ar(1), nm(1), and the Info entries for @file{binutils}.
1941 @cindex section sizes
1943 @c man title size list section sizes and total size.
1946 @c man begin SYNOPSIS size
1947 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1949 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1950 [@option{-t}|@option{--totals}]
1951 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1952 [@var{objfile}@dots{}]
1956 @c man begin DESCRIPTION size
1958 The @sc{gnu} @command{size} utility lists the section sizes---and the total
1959 size---for each of the object or archive files @var{objfile} in its
1960 argument list. By default, one line of output is generated for each
1961 object file or each module in an archive.
1963 @var{objfile}@dots{} are the object files to be examined.
1964 If none are specified, the file @code{a.out} will be used.
1968 @c man begin OPTIONS size
1970 The command line options have the following meanings:
1975 @itemx --format=@var{compatibility}
1976 @cindex @command{size} display format
1977 Using one of these options, you can choose whether the output from @sc{gnu}
1978 @command{size} resembles output from System V @command{size} (using @option{-A},
1979 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
1980 @option{--format=berkeley}). The default is the one-line format similar to
1982 @c Bonus for doc-source readers: you can also say --format=strange (or
1983 @c anything else that starts with 's') for sysv, and --format=boring (or
1984 @c anything else that starts with 'b') for Berkeley.
1986 Here is an example of the Berkeley (default) format of output from
1989 $ size --format=Berkeley ranlib size
1990 text data bss dec hex filename
1991 294880 81920 11592 388392 5ed28 ranlib
1992 294880 81920 11888 388688 5ee50 size
1996 This is the same data, but displayed closer to System V conventions:
1999 $ size --format=SysV ranlib size
2017 Show a summary of acceptable arguments and options.
2022 @itemx --radix=@var{number}
2023 @cindex @command{size} number format
2024 @cindex radix for section sizes
2025 Using one of these options, you can control whether the size of each
2026 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2027 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2028 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2029 values (8, 10, 16) are supported. The total size is always given in two
2030 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2031 octal and hexadecimal if you're using @option{-o}.
2035 Show totals of all objects listed (Berkeley format listing mode only).
2037 @item --target=@var{bfdname}
2038 @cindex object code format
2039 Specify that the object-code format for @var{objfile} is
2040 @var{bfdname}. This option may not be necessary; @command{size} can
2041 automatically recognize many formats.
2042 @xref{Target Selection}, for more information.
2046 Display the version number of @command{size}.
2052 @c man begin SEEALSO size
2053 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2060 @cindex listings strings
2061 @cindex printing strings
2062 @cindex strings, printing
2064 @c man title strings print the strings of printable characters in files.
2067 @c man begin SYNOPSIS strings
2068 strings [@option{-afov}] [@option{-}@var{min-len}]
2069 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2070 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2071 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2072 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2073 [@option{--target=}@var{bfdname}]
2074 [@option{--help}] [@option{--version}] @var{file}@dots{}
2078 @c man begin DESCRIPTION strings
2080 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2081 character sequences that are at least 4 characters long (or the number
2082 given with the options below) and are followed by an unprintable
2083 character. By default, it only prints the strings from the initialized
2084 and loaded sections of object files; for other types of files, it prints
2085 the strings from the whole file.
2087 @command{strings} is mainly useful for determining the contents of non-text
2092 @c man begin OPTIONS strings
2098 Do not scan only the initialized and loaded sections of object files;
2099 scan the whole files.
2102 @itemx --print-file-name
2103 Print the name of the file before each string.
2106 Print a summary of the program usage on the standard output and exit.
2108 @item -@var{min-len}
2109 @itemx -n @var{min-len}
2110 @itemx --bytes=@var{min-len}
2111 Print sequences of characters that are at least @var{min-len} characters
2112 long, instead of the default 4.
2115 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2116 act like @samp{-t d} instead. Since we can not be compatible with both
2117 ways, we simply chose one.
2119 @item -t @var{radix}
2120 @itemx --radix=@var{radix}
2121 Print the offset within the file before each string. The single
2122 character argument specifies the radix of the offset---@samp{o} for
2123 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2125 @item -e @var{encoding}
2126 @itemx --encoding=@var{encoding}
2127 Select the character encoding of the strings that are to be found.
2128 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2129 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2130 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2131 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2132 littleendian. Useful for finding wide character strings.
2134 @item --target=@var{bfdname}
2135 @cindex object code format
2136 Specify an object code format other than your system's default format.
2137 @xref{Target Selection}, for more information.
2141 Print the program version number on the standard output and exit.
2147 @c man begin SEEALSO strings
2148 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2149 and the Info entries for @file{binutils}.
2157 @cindex removing symbols
2158 @cindex discarding symbols
2159 @cindex symbols, discarding
2161 @c man title strip Discard symbols from object files.
2164 @c man begin SYNOPSIS strip
2165 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2166 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2167 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2168 [@option{-s}|@option{--strip-all}]
2169 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2170 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2171 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2172 [@option{-w}|@option{--wildcard}]
2173 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2174 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2175 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2176 [@option{--only-keep-debug}]
2177 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2178 [@option{--help}] [@option{--info}]
2179 @var{objfile}@dots{}
2183 @c man begin DESCRIPTION strip
2185 @sc{gnu} @command{strip} discards all symbols from object files
2186 @var{objfile}. The list of object files may include archives.
2187 At least one object file must be given.
2189 @command{strip} modifies the files named in its argument,
2190 rather than writing modified copies under different names.
2194 @c man begin OPTIONS strip
2197 @item -F @var{bfdname}
2198 @itemx --target=@var{bfdname}
2199 Treat the original @var{objfile} as a file with the object
2200 code format @var{bfdname}, and rewrite it in the same format.
2201 @xref{Target Selection}, for more information.
2204 Show a summary of the options to @command{strip} and exit.
2207 Display a list showing all architectures and object formats available.
2209 @item -I @var{bfdname}
2210 @itemx --input-target=@var{bfdname}
2211 Treat the original @var{objfile} as a file with the object
2212 code format @var{bfdname}.
2213 @xref{Target Selection}, for more information.
2215 @item -O @var{bfdname}
2216 @itemx --output-target=@var{bfdname}
2217 Replace @var{objfile} with a file in the output format @var{bfdname}.
2218 @xref{Target Selection}, for more information.
2220 @item -R @var{sectionname}
2221 @itemx --remove-section=@var{sectionname}
2222 Remove any section named @var{sectionname} from the output file. This
2223 option may be given more than once. Note that using this option
2224 inappropriately may make the output file unusable.
2233 @itemx --strip-debug
2234 Remove debugging symbols only.
2236 @item --strip-unneeded
2237 Remove all symbols that are not needed for relocation processing.
2239 @item -K @var{symbolname}
2240 @itemx --keep-symbol=@var{symbolname}
2241 Keep only symbol @var{symbolname} from the source file. This option may
2242 be given more than once.
2244 @item -N @var{symbolname}
2245 @itemx --strip-symbol=@var{symbolname}
2246 Remove symbol @var{symbolname} from the source file. This option may be
2247 given more than once, and may be combined with strip options other than
2251 Put the stripped output in @var{file}, rather than replacing the
2252 existing file. When this argument is used, only one @var{objfile}
2253 argument may be specified.
2256 @itemx --preserve-dates
2257 Preserve the access and modification dates of the file.
2261 Permit regular expressions in @var{symbolname}s used in other command
2262 line options. The question mark (?), asterisk (*), backslash (\) and
2263 square brackets ([]) operators can be used anywhere in the symbol
2264 name. If the first character of the symbol name is the exclamation
2265 point (!) then the sense of the switch is reversed for that symbol.
2272 would cause strip to only keep symbols that start with the letters
2273 ``fo'', but to discard the symbol ``foo''.
2276 @itemx --discard-all
2277 Remove non-global symbols.
2280 @itemx --discard-locals
2281 Remove compiler-generated local symbols.
2282 (These usually start with @samp{L} or @samp{.}.)
2284 @item --only-keep-debug
2285 Strip a file, removing any sections that would be stripped by
2286 @option{--strip-debug} and leaving the debugging sections.
2288 The intention is that this option will be used in conjunction with
2289 @option{--add-gnu-debuglink} to create a two part executable. One a
2290 stripped binary which will occupy less space in RAM and in a
2291 distribution and the second a debugging information file which is only
2292 needed if debugging abilities are required. The suggested procedure
2293 to create these files is as follows:
2296 @item Link the executable as normal. Assuming that is is called
2298 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2299 create a file containing the debugging info.
2300 @item Run @code{objcopy --strip-debug foo} to create a
2301 stripped executable.
2302 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2303 to add a link to the debugging info into the stripped executable.
2306 Note - the choice of @code{.dbg} as an extension for the debug info
2307 file is arbitrary. Also the @code{--only-keep-debug} step is
2308 optional. You could instead do this:
2311 @item Link the executable as normal.
2312 @item Copy @code{foo} to @code{foo.full}
2313 @item Run @code{strip --strip-debug foo}
2314 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2317 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2318 full executable. It does not have to be a file created by the
2319 @option{--only-keep-debug} switch.
2323 Show the version number for @command{strip}.
2327 Verbose output: list all object files modified. In the case of
2328 archives, @samp{strip -v} lists all members of the archive.
2334 @c man begin SEEALSO strip
2335 the Info entries for @file{binutils}.
2339 @node c++filt, addr2line, strip, Top
2343 @cindex demangling C++ symbols
2345 @c man title cxxfilt Demangle C++ and Java symbols.
2348 @c man begin SYNOPSIS cxxfilt
2349 c++filt [@option{-_}|@option{--strip-underscores}]
2350 [@option{-j}|@option{--java}]
2351 [@option{-n}|@option{--no-strip-underscores}]
2352 [@option{-p}|@option{--no-params}]
2353 [@option{-s} @var{format}|@option{--format=}@var{format}]
2354 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2358 @c man begin DESCRIPTION cxxfilt
2361 The C++ and Java languages provides function overloading, which means
2362 that you can write many functions with the same name (providing each
2363 takes parameters of different types). All C++ and Java function names
2364 are encoded into a low-level assembly label (this process is known as
2365 @dfn{mangling}). The @command{c++filt}
2366 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2367 MS-DOS this program is named @command{cxxfilt}.}
2368 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2369 names into user-level names so that the linker can keep these overloaded
2370 functions from clashing.
2372 Every alphanumeric word (consisting of letters, digits, underscores,
2373 dollars, or periods) seen in the input is a potential label. If the
2374 label decodes into a C++ name, the C++ name replaces the low-level
2377 You can use @command{c++filt} to decipher individual symbols:
2380 c++filt @var{symbol}
2383 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2384 names from the standard input and writes the demangled names to the
2385 standard output. All results are printed on the standard output.
2389 @c man begin OPTIONS cxxfilt
2393 @itemx --strip-underscores
2394 On some systems, both the C and C++ compilers put an underscore in front
2395 of every name. For example, the C name @code{foo} gets the low-level
2396 name @code{_foo}. This option removes the initial underscore. Whether
2397 @command{c++filt} removes the underscore by default is target dependent.
2401 Prints demangled names using Java syntax. The default is to use C++
2405 @itemx --no-strip-underscores
2406 Do not remove the initial underscore.
2410 When demangling the name of a function, do not display the types of
2411 the function's parameters.
2413 @item -s @var{format}
2414 @itemx --format=@var{format}
2415 @command{c++filt} can decode various methods of mangling, used by
2416 different compilers. The argument to this option selects which
2421 Automatic selection based on executable (the default method)
2423 the one used by the @sc{gnu} C++ compiler (g++)
2425 the one used by the Lucid compiler (lcc)
2427 the one specified by the C++ Annotated Reference Manual
2429 the one used by the HP compiler (aCC)
2431 the one used by the EDG compiler
2433 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2435 the one used by the @sc{gnu} Java compiler (gcj)
2437 the one used by the @sc{gnu} Ada compiler (GNAT).
2441 Print a summary of the options to @command{c++filt} and exit.
2444 Print the version number of @command{c++filt} and exit.
2450 @c man begin SEEALSO cxxfilt
2451 the Info entries for @file{binutils}.
2456 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2457 user interface are subject to change in future releases. In particular,
2458 a command-line option may be required in the the future to decode a name
2459 passed as an argument on the command line; in other words,
2462 c++filt @var{symbol}
2466 may in a future release become
2469 c++filt @var{option} @var{symbol}
2477 @cindex address to file name and line number
2479 @c man title addr2line convert addresses into file names and line numbers.
2482 @c man begin SYNOPSIS addr2line
2483 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2484 [@option{-C}|@option{--demangle}[=@var{style}]]
2485 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2486 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2487 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2492 @c man begin DESCRIPTION addr2line
2494 @command{addr2line} translates program addresses into file names and line
2495 numbers. Given an address and an executable, it uses the debugging
2496 information in the executable to figure out which file name and line
2497 number are associated with a given address.
2499 The executable to use is specified with the @option{-e} option. The
2500 default is the file @file{a.out}.
2502 @command{addr2line} has two modes of operation.
2504 In the first, hexadecimal addresses are specified on the command line,
2505 and @command{addr2line} displays the file name and line number for each
2508 In the second, @command{addr2line} reads hexadecimal addresses from
2509 standard input, and prints the file name and line number for each
2510 address on standard output. In this mode, @command{addr2line} may be used
2511 in a pipe to convert dynamically chosen addresses.
2513 The format of the output is @samp{FILENAME:LINENO}. The file name and
2514 line number for each address is printed on a separate line. If the
2515 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2516 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2517 containing the address.
2519 If the file name or function name can not be determined,
2520 @command{addr2line} will print two question marks in their place. If the
2521 line number can not be determined, @command{addr2line} will print 0.
2525 @c man begin OPTIONS addr2line
2527 The long and short forms of options, shown here as alternatives, are
2531 @item -b @var{bfdname}
2532 @itemx --target=@var{bfdname}
2533 @cindex object code format
2534 Specify that the object-code format for the object files is
2538 @itemx --demangle[=@var{style}]
2539 @cindex demangling in objdump
2540 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2541 Besides removing any initial underscore prepended by the system, this
2542 makes C++ function names readable. Different compilers have different
2543 mangling styles. The optional demangling style argument can be used to
2544 choose an appropriate demangling style for your compiler. @xref{c++filt},
2545 for more information on demangling.
2547 @item -e @var{filename}
2548 @itemx --exe=@var{filename}
2549 Specify the name of the executable for which addresses should be
2550 translated. The default file is @file{a.out}.
2554 Display function names as well as file and line number information.
2558 Display only the base of each file name.
2564 @c man begin SEEALSO addr2line
2565 Info entries for @file{binutils}.
2572 @command{nlmconv} converts a relocatable object file into a NetWare
2576 @command{nlmconv} currently works with @samp{i386} object
2577 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2578 object files in @sc{elf}, or @code{a.out} format@footnote{
2579 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2580 format in the Binary File Descriptor library. It has only been tested
2581 with the above formats.}.
2585 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2586 utilities, since it is only useful for NLM targets.
2589 @c man title nlmconv converts object code into an NLM.
2592 @c man begin SYNOPSIS nlmconv
2593 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2594 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2595 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2596 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2597 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2598 @var{infile} @var{outfile}
2602 @c man begin DESCRIPTION nlmconv
2604 @command{nlmconv} converts the relocatable @samp{i386} object file
2605 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2606 reading @var{headerfile} for NLM header information. For instructions
2607 on writing the NLM command file language used in header files, see the
2608 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2609 Development and Tools Overview}, which is part of the NLM Software
2610 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2611 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2614 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2617 @command{nlmconv} can perform a link step. In other words, you can list
2618 more than one object file for input if you list them in the definitions
2619 file (rather than simply specifying one input file on the command line).
2620 In this case, @command{nlmconv} calls the linker for you.
2624 @c man begin OPTIONS nlmconv
2627 @item -I @var{bfdname}
2628 @itemx --input-target=@var{bfdname}
2629 Object format of the input file. @command{nlmconv} can usually determine
2630 the format of a given file (so no default is necessary).
2631 @xref{Target Selection}, for more information.
2633 @item -O @var{bfdname}
2634 @itemx --output-target=@var{bfdname}
2635 Object format of the output file. @command{nlmconv} infers the output
2636 format based on the input format, e.g. for a @samp{i386} input file the
2637 output format is @samp{nlm32-i386}.
2638 @xref{Target Selection}, for more information.
2640 @item -T @var{headerfile}
2641 @itemx --header-file=@var{headerfile}
2642 Reads @var{headerfile} for NLM header information. For instructions on
2643 writing the NLM command file language used in header files, see@ see the
2644 @samp{linkers} section, of the @cite{NLM Development and Tools
2645 Overview}, which is part of the NLM Software Developer's Kit, available
2650 Displays (on standard error) the linker command line used by @command{nlmconv}.
2652 @item -l @var{linker}
2653 @itemx --linker=@var{linker}
2654 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2659 Prints a usage summary.
2663 Prints the version number for @command{nlmconv}.
2669 @c man begin SEEALSO nlmconv
2670 the Info entries for @file{binutils}.
2677 @command{windres} may be used to manipulate Windows resources.
2680 @emph{Warning:} @command{windres} is not always built as part of the binary
2681 utilities, since it is only useful for Windows targets.
2684 @c man title windres manipulate Windows resources.
2687 @c man begin SYNOPSIS windres
2688 windres [options] [input-file] [output-file]
2692 @c man begin DESCRIPTION windres
2694 @command{windres} reads resources from an input file and copies them into
2695 an output file. Either file may be in one of three formats:
2699 A text format read by the Resource Compiler.
2702 A binary format generated by the Resource Compiler.
2705 A COFF object or executable.
2708 The exact description of these different formats is available in
2709 documentation from Microsoft.
2711 When @command{windres} converts from the @code{rc} format to the @code{res}
2712 format, it is acting like the Windows Resource Compiler. When
2713 @command{windres} converts from the @code{res} format to the @code{coff}
2714 format, it is acting like the Windows @code{CVTRES} program.
2716 When @command{windres} generates an @code{rc} file, the output is similar
2717 but not identical to the format expected for the input. When an input
2718 @code{rc} file refers to an external filename, an output @code{rc} file
2719 will instead include the file contents.
2721 If the input or output format is not specified, @command{windres} will
2722 guess based on the file name, or, for the input file, the file contents.
2723 A file with an extension of @file{.rc} will be treated as an @code{rc}
2724 file, a file with an extension of @file{.res} will be treated as a
2725 @code{res} file, and a file with an extension of @file{.o} or
2726 @file{.exe} will be treated as a @code{coff} file.
2728 If no output file is specified, @command{windres} will print the resources
2729 in @code{rc} format to standard output.
2731 The normal use is for you to write an @code{rc} file, use @command{windres}
2732 to convert it to a COFF object file, and then link the COFF file into
2733 your application. This will make the resources described in the
2734 @code{rc} file available to Windows.
2738 @c man begin OPTIONS windres
2741 @item -i @var{filename}
2742 @itemx --input @var{filename}
2743 The name of the input file. If this option is not used, then
2744 @command{windres} will use the first non-option argument as the input file
2745 name. If there are no non-option arguments, then @command{windres} will
2746 read from standard input. @command{windres} can not read a COFF file from
2749 @item -o @var{filename}
2750 @itemx --output @var{filename}
2751 The name of the output file. If this option is not used, then
2752 @command{windres} will use the first non-option argument, after any used
2753 for the input file name, as the output file name. If there is no
2754 non-option argument, then @command{windres} will write to standard output.
2755 @command{windres} can not write a COFF file to standard output. Note,
2756 for compatability with @command{rc} the option @option{-fo} is also
2757 accepted, but its use is not recommended.
2759 @item -J @var{format}
2760 @itemx --input-format @var{format}
2761 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2762 @samp{coff}. If no input format is specified, @command{windres} will
2763 guess, as described above.
2765 @item -O @var{format}
2766 @itemx --output-format @var{format}
2767 The output format to generate. @var{format} may be @samp{res},
2768 @samp{rc}, or @samp{coff}. If no output format is specified,
2769 @command{windres} will guess, as described above.
2771 @item -F @var{target}
2772 @itemx --target @var{target}
2773 Specify the BFD format to use for a COFF file as input or output. This
2774 is a BFD target name; you can use the @option{--help} option to see a list
2775 of supported targets. Normally @command{windres} will use the default
2776 format, which is the first one listed by the @option{--help} option.
2778 @ref{Target Selection}.
2781 @item --preprocessor @var{program}
2782 When @command{windres} reads an @code{rc} file, it runs it through the C
2783 preprocessor first. This option may be used to specify the preprocessor
2784 to use, including any leading arguments. The default preprocessor
2785 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2787 @item -I @var{directory}
2788 @itemx --include-dir @var{directory}
2789 Specify an include directory to use when reading an @code{rc} file.
2790 @command{windres} will pass this to the preprocessor as an @option{-I}
2791 option. @command{windres} will also search this directory when looking for
2792 files named in the @code{rc} file. If the argument passed to this command
2793 matches any of the supported @var{formats} (as descrived in the @option{-J}
2794 option), it will issue a deprecation warning, and behave just like the
2795 @option{-J} option. New programs should not use this behaviour. If a
2796 directory happens to match a @var{format}, simple prefix it with @samp{./}
2797 to disable the backward compatibility.
2799 @item -D @var{target}
2800 @itemx --define @var{sym}[=@var{val}]
2801 Specify a @option{-D} option to pass to the preprocessor when reading an
2804 @item -U @var{target}
2805 @itemx --undefine @var{sym}
2806 Specify a @option{-U} option to pass to the preprocessor when reading an
2810 Ignored for compatibility with rc.
2813 Enable verbose mode. This tells you what the preprocessor is if you
2817 @item --language @var{val}
2818 Specify the default language to use when reading an @code{rc} file.
2819 @var{val} should be a hexadecimal language code. The low eight bits are
2820 the language, and the high eight bits are the sublanguage.
2822 @item --use-temp-file
2823 Use a temporary file to instead of using popen to read the output of
2824 the preprocessor. Use this option if the popen implementation is buggy
2825 on the host (eg., certain non-English language versions of Windows 95 and
2826 Windows 98 are known to have buggy popen where the output will instead
2829 @item --no-use-temp-file
2830 Use popen, not a temporary file, to read the output of the preprocessor.
2831 This is the default behaviour.
2835 Prints a usage summary.
2839 Prints the version number for @command{windres}.
2842 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2843 this will turn on parser debugging.
2849 @c man begin SEEALSO windres
2850 the Info entries for @file{binutils}.
2855 @chapter Create files needed to build and use DLLs
2859 @command{dlltool} may be used to create the files needed to build and use
2860 dynamic link libraries (DLLs).
2863 @emph{Warning:} @command{dlltool} is not always built as part of the binary
2864 utilities, since it is only useful for those targets which support DLLs.
2867 @c man title dlltool Create files needed to build and use DLLs.
2870 @c man begin SYNOPSIS dlltool
2871 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2872 [@option{-b}|@option{--base-file} @var{base-file-name}]
2873 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2874 [@option{-z}|@option{--output-def} @var{def-file-name}]
2875 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2876 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2877 [@option{--exclude-symbols} @var{list}]
2878 [@option{--no-default-excludes}]
2879 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2880 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2881 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2882 [@option{-A}|@option{--add-stdcall-alias}]
2883 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
2884 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2885 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
2886 [@option{-v}|@option{--verbose}]
2887 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2888 [object-file @dots{}]
2892 @c man begin DESCRIPTION dlltool
2894 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2895 @option{-b} options as well as object files specified on the command
2896 line. It then processes these inputs and if the @option{-e} option has
2897 been specified it creates a exports file. If the @option{-l} option
2898 has been specified it creates a library file and if the @option{-z} option
2899 has been specified it creates a def file. Any or all of the @option{-e},
2900 @option{-l} and @option{-z} options can be present in one invocation of
2903 When creating a DLL, along with the source for the DLL, it is necessary
2904 to have three other files. @command{dlltool} can help with the creation of
2907 The first file is a @samp{.def} file which specifies which functions are
2908 exported from the DLL, which functions the DLL imports, and so on. This
2909 is a text file and can be created by hand, or @command{dlltool} can be used
2910 to create it using the @option{-z} option. In this case @command{dlltool}
2911 will scan the object files specified on its command line looking for
2912 those functions which have been specially marked as being exported and
2913 put entries for them in the .def file it creates.
2915 In order to mark a function as being exported from a DLL, it needs to
2916 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2917 section of the object file. This can be done in C by using the
2921 asm (".section .drectve");
2922 asm (".ascii \"-export:my_func\"");
2924 int my_func (void) @{ @dots{} @}
2927 The second file needed for DLL creation is an exports file. This file
2928 is linked with the object files that make up the body of the DLL and it
2929 handles the interface between the DLL and the outside world. This is a
2930 binary file and it can be created by giving the @option{-e} option to
2931 @command{dlltool} when it is creating or reading in a .def file.
2933 The third file needed for DLL creation is the library file that programs
2934 will link with in order to access the functions in the DLL. This file
2935 can be created by giving the @option{-l} option to dlltool when it
2936 is creating or reading in a .def file.
2938 @command{dlltool} builds the library file by hand, but it builds the
2939 exports file by creating temporary files containing assembler statements
2940 and then assembling these. The @option{-S} command line option can be
2941 used to specify the path to the assembler that dlltool will use,
2942 and the @option{-f} option can be used to pass specific flags to that
2943 assembler. The @option{-n} can be used to prevent dlltool from deleting
2944 these temporary assembler files when it is done, and if @option{-n} is
2945 specified twice then this will prevent dlltool from deleting the
2946 temporary object files it used to build the library.
2948 Here is an example of creating a DLL from a source file @samp{dll.c} and
2949 also creating a program (from an object file called @samp{program.o})
2954 dlltool -e exports.o -l dll.lib dll.o
2955 gcc dll.o exports.o -o dll.dll
2956 gcc program.o dll.lib -o program
2961 @c man begin OPTIONS dlltool
2963 The command line options have the following meanings:
2967 @item -d @var{filename}
2968 @itemx --input-def @var{filename}
2969 @cindex input .def file
2970 Specifies the name of a .def file to be read in and processed.
2972 @item -b @var{filename}
2973 @itemx --base-file @var{filename}
2975 Specifies the name of a base file to be read in and processed. The
2976 contents of this file will be added to the relocation section in the
2977 exports file generated by dlltool.
2979 @item -e @var{filename}
2980 @itemx --output-exp @var{filename}
2981 Specifies the name of the export file to be created by dlltool.
2983 @item -z @var{filename}
2984 @itemx --output-def @var{filename}
2985 Specifies the name of the .def file to be created by dlltool.
2987 @item -l @var{filename}
2988 @itemx --output-lib @var{filename}
2989 Specifies the name of the library file to be created by dlltool.
2991 @item --export-all-symbols
2992 Treat all global and weak defined symbols found in the input object
2993 files as symbols to be exported. There is a small list of symbols which
2994 are not exported by default; see the @option{--no-default-excludes}
2995 option. You may add to the list of symbols to not export by using the
2996 @option{--exclude-symbols} option.
2998 @item --no-export-all-symbols
2999 Only export symbols explicitly listed in an input .def file or in
3000 @samp{.drectve} sections in the input object files. This is the default
3001 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3002 attributes in the source code.
3004 @item --exclude-symbols @var{list}
3005 Do not export the symbols in @var{list}. This is a list of symbol names
3006 separated by comma or colon characters. The symbol names should not
3007 contain a leading underscore. This is only meaningful when
3008 @option{--export-all-symbols} is used.
3010 @item --no-default-excludes
3011 When @option{--export-all-symbols} is used, it will by default avoid
3012 exporting certain special symbols. The current list of symbols to avoid
3013 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3014 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3015 to go ahead and export these special symbols. This is only meaningful
3016 when @option{--export-all-symbols} is used.
3019 @itemx --as @var{path}
3020 Specifies the path, including the filename, of the assembler to be used
3021 to create the exports file.
3023 @item -f @var{options}
3024 @itemx --as-flags @var{options}
3025 Specifies any specific command line options to be passed to the
3026 assembler when building the exports file. This option will work even if
3027 the @option{-S} option is not used. This option only takes one argument,
3028 and if it occurs more than once on the command line, then later
3029 occurrences will override earlier occurrences. So if it is necessary to
3030 pass multiple options to the assembler they should be enclosed in
3034 @itemx --dll-name @var{name}
3035 Specifies the name to be stored in the .def file as the name of the DLL
3036 when the @option{-e} option is used. If this option is not present, then
3037 the filename given to the @option{-e} option will be used as the name of
3040 @item -m @var{machine}
3041 @itemx -machine @var{machine}
3042 Specifies the type of machine for which the library file should be
3043 built. @command{dlltool} has a built in default type, depending upon how
3044 it was created, but this option can be used to override that. This is
3045 normally only useful when creating DLLs for an ARM processor, when the
3046 contents of the DLL are actually encode using Thumb instructions.
3049 @itemx --add-indirect
3050 Specifies that when @command{dlltool} is creating the exports file it
3051 should add a section which allows the exported functions to be
3052 referenced without using the import library. Whatever the hell that
3056 @itemx --add-underscore
3057 Specifies that when @command{dlltool} is creating the exports file it
3058 should prepend an underscore to the names of the exported functions.
3062 Specifies that when @command{dlltool} is creating the exports file it
3063 should not append the string @samp{@@ <number>}. These numbers are
3064 called ordinal numbers and they represent another way of accessing the
3065 function in a DLL, other than by name.
3068 @itemx --add-stdcall-alias
3069 Specifies that when @command{dlltool} is creating the exports file it
3070 should add aliases for stdcall symbols without @samp{@@ <number>}
3071 in addition to the symbols with @samp{@@ <number>}.
3074 @itemx --ext-prefix-alias @var{prefix}
3075 Causes @command{dlltool} to create external aliases for all DLL
3076 imports with the specified prefix. The aliases are created for both
3077 external and import symbols with no leading underscore.
3081 Specifies that when @command{dlltool} is creating the exports and library
3082 files it should omit the @code{.idata4} section. This is for compatibility
3083 with certain operating systems.
3087 Specifies that when @command{dlltool} is creating the exports and library
3088 files it should omit the @code{.idata5} section. This is for compatibility
3089 with certain operating systems.
3093 Specifies that @command{dlltool} should mark the objects in the library
3094 file and exports file that it produces as supporting interworking
3095 between ARM and Thumb code.
3099 Makes @command{dlltool} preserve the temporary assembler files it used to
3100 create the exports file. If this option is repeated then dlltool will
3101 also preserve the temporary object files it uses to create the library
3104 @item -t @var{prefix}
3105 @itemx --temp-prefix @var{prefix}
3106 Makes @command{dlltool} use @var{prefix} when constructing the names of
3107 temporary assembler and object files. By default, the temp file prefix
3108 is generated from the pid.
3112 Make dlltool describe what it is doing.
3116 Displays a list of command line options and then exits.
3120 Displays dlltool's version number and then exits.
3127 @c man begin SEEALSO dlltool
3128 the Info entries for @file{binutils}.
3135 @cindex ELF file information
3138 @c man title readelf Displays information about ELF files.
3141 @c man begin SYNOPSIS readelf
3142 readelf [@option{-a}|@option{--all}]
3143 [@option{-h}|@option{--file-header}]
3144 [@option{-l}|@option{--program-headers}|@option{--segments}]
3145 [@option{-S}|@option{--section-headers}|@option{--sections}]
3146 [@option{-e}|@option{--headers}]
3147 [@option{-s}|@option{--syms}|@option{--symbols}]
3148 [@option{-n}|@option{--notes}]
3149 [@option{-r}|@option{--relocs}]
3150 [@option{-u}|@option{--unwind}]
3151 [@option{-d}|@option{--dynamic}]
3152 [@option{-V}|@option{--version-info}]
3153 [@option{-A}|@option{--arch-specific}]
3154 [@option{-D}|@option{--use-dynamic}]
3155 [@option{-x} <number>|@option{--hex-dump=}<number>]
3156 [@option{-w[liaprmfFso]}|
3157 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]]
3158 [@option{-I}|@option{-histogram}]
3159 [@option{-v}|@option{--version}]
3160 [@option{-W}|@option{--wide}]
3161 [@option{-H}|@option{--help}]
3162 @var{elffile}@dots{}
3166 @c man begin DESCRIPTION readelf
3168 @command{readelf} displays information about one or more ELF format object
3169 files. The options control what particular information to display.
3171 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3172 64-bit ELF files are supported, as are archives containing ELF files.
3174 This program performs a similar function to @command{objdump} but it
3175 goes into more detail and it exists independently of the @sc{bfd}
3176 library, so if there is a bug in @sc{bfd} then readelf will not be
3181 @c man begin OPTIONS readelf
3183 The long and short forms of options, shown here as alternatives, are
3184 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3190 Equivalent to specifiying @option{--file-header},
3191 @option{--program-headers}, @option{--sections}, @option{--symbols},
3192 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3193 @option{--version-info}.
3196 @itemx --file-header
3197 @cindex ELF file header information
3198 Displays the information contained in the ELF header at the start of the
3202 @itemx --program-headers
3204 @cindex ELF program header information
3205 @cindex ELF segment information
3206 Displays the information contained in the file's segment headers, if it
3211 @itemx --section-headers
3212 @cindex ELF section information
3213 Displays the information contained in the file's section headers, if it
3219 @cindex ELF symbol table information
3220 Displays the entries in symbol table section of the file, if it has one.
3224 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3229 Displays the contents of the NOTE segments and/or sections, if any.
3233 @cindex ELF reloc information
3234 Displays the contents of the file's relocation section, if it has one.
3238 @cindex unwind information
3239 Displays the contents of the file's unwind section, if it has one. Only
3240 the unwind sections for IA64 ELF files are currently supported.
3244 @cindex unwind information
3245 Displays the contents of the file's unwind section, if it has one. Only
3246 the unwind sections for IA64 ELF files are currently supported.
3250 @cindex ELF dynamic section information
3251 Displays the contents of the file's dynamic section, if it has one.
3254 @itemx --version-info
3255 @cindex ELF version sections informations
3256 Displays the contents of the version sections in the file, it they
3260 @itemx --arch-specific
3261 Displays architecture-specific information in the file, if there
3265 @itemx --use-dynamic
3266 When displaying symbols, this option makes @command{readelf} use the
3267 symbol table in the file's dynamic section, rather than the one in the
3271 @itemx --hex-dump=<number>
3272 Displays the contents of the indicated section as a hexadecimal dump.
3274 @item -w[liaprmfFso]
3275 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]
3276 Displays the contents of the debug sections in the file, if any are
3277 present. If one of the optional letters or words follows the switch
3278 then only data found in those specific sections will be dumped.
3282 Display a histogram of bucket list lengths when displaying the contents
3283 of the symbol tables.
3287 Display the version number of readelf.
3291 Don't break output lines to fit into 80 columns. By default
3292 @command{readelf} breaks section header and segment listing lines for
3293 64-bit ELF files, so that they fit into 80 columns. This option causes
3294 @command{readelf} to print each section header resp. each segment one a
3295 single line, which is far more readable on terminals wider than 80 columns.
3299 Display the command line options understood by @command{readelf}.
3306 @c man begin SEEALSO readelf
3307 objdump(1), and the Info entries for @file{binutils}.
3311 @node Selecting The Target System
3312 @chapter Selecting the Target System
3314 You can specify two aspects of the target system to the @sc{gnu}
3315 binary file utilities, each in several ways:
3325 In the following summaries, the lists of ways to specify values are in
3326 order of decreasing precedence. The ways listed first override those
3329 The commands to list valid values only list the values for which the
3330 programs you are running were configured. If they were configured with
3331 @option{--enable-targets=all}, the commands list most of the available
3332 values, but a few are left out; not all targets can be configured in at
3333 once because some of them can only be configured @dfn{native} (on hosts
3334 with the same type as the target system).
3337 * Target Selection::
3338 * Architecture Selection::
3341 @node Target Selection
3342 @section Target Selection
3344 A @dfn{target} is an object file format. A given target may be
3345 supported for multiple architectures (@pxref{Architecture Selection}).
3346 A target selection may also have variations for different operating
3347 systems or architectures.
3349 The command to list valid target values is @samp{objdump -i}
3350 (the first column of output contains the relevant information).
3352 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3353 @samp{a.out-sunos-big}.
3355 You can also specify a target using a configuration triplet. This is
3356 the same sort of name that is passed to @file{configure} to specify a
3357 target. When you use a configuration triplet as an argument, it must be
3358 fully canonicalized. You can see the canonical version of a triplet by
3359 running the shell script @file{config.sub} which is included with the
3362 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3363 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3365 @subheading @command{objdump} Target
3371 command line option: @option{-b} or @option{--target}
3374 environment variable @code{GNUTARGET}
3377 deduced from the input file
3380 @subheading @command{objcopy} and @command{strip} Input Target
3386 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3389 environment variable @code{GNUTARGET}
3392 deduced from the input file
3395 @subheading @command{objcopy} and @command{strip} Output Target
3401 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3404 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3407 environment variable @code{GNUTARGET}
3410 deduced from the input file
3413 @subheading @command{nm}, @command{size}, and @command{strings} Target
3419 command line option: @option{--target}
3422 environment variable @code{GNUTARGET}
3425 deduced from the input file
3428 @node Architecture Selection
3429 @section Architecture Selection
3431 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3432 to run. Its name may contain a colon, separating the name of the
3433 processor family from the name of the particular @sc{cpu}.
3435 The command to list valid architecture values is @samp{objdump -i} (the
3436 second column contains the relevant information).
3438 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3440 @subheading @command{objdump} Architecture
3446 command line option: @option{-m} or @option{--architecture}
3449 deduced from the input file
3452 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3458 deduced from the input file
3461 @node Reporting Bugs
3462 @chapter Reporting Bugs
3464 @cindex reporting bugs
3466 Your bug reports play an essential role in making the binary utilities
3469 Reporting a bug may help you by bringing a solution to your problem, or
3470 it may not. But in any case the principal function of a bug report is
3471 to help the entire community by making the next version of the binary
3472 utilities work better. Bug reports are your contribution to their
3475 In order for a bug report to serve its purpose, you must include the
3476 information that enables us to fix the bug.
3479 * Bug Criteria:: Have you found a bug?
3480 * Bug Reporting:: How to report bugs
3484 @section Have You Found a Bug?
3485 @cindex bug criteria
3487 If you are not sure whether you have found a bug, here are some guidelines:
3490 @cindex fatal signal
3493 If a binary utility gets a fatal signal, for any input whatever, that is
3494 a bug. Reliable utilities never crash.
3496 @cindex error on valid input
3498 If a binary utility produces an error message for valid input, that is a
3502 If you are an experienced user of binary utilities, your suggestions for
3503 improvement are welcome in any case.
3507 @section How to Report Bugs
3509 @cindex bugs, reporting
3511 A number of companies and individuals offer support for @sc{gnu}
3512 products. If you obtained the binary utilities from a support
3513 organization, we recommend you contact that organization first.
3515 You can find contact information for many support companies and
3516 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3519 In any event, we also recommend that you send bug reports for the binary
3520 utilities to @samp{bug-binutils@@gnu.org}.
3522 The fundamental principle of reporting bugs usefully is this:
3523 @strong{report all the facts}. If you are not sure whether to state a
3524 fact or leave it out, state it!
3526 Often people omit facts because they think they know what causes the
3527 problem and assume that some details do not matter. Thus, you might
3528 assume that the name of a file you use in an example does not matter.
3529 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3530 a stray memory reference which happens to fetch from the location where
3531 that pathname is stored in memory; perhaps, if the pathname were
3532 different, the contents of that location would fool the utility into
3533 doing the right thing despite the bug. Play it safe and give a
3534 specific, complete example. That is the easiest thing for you to do,
3535 and the most helpful.
3537 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3538 it is new to us. Therefore, always write your bug reports on the assumption
3539 that the bug has not been reported previously.
3541 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3542 bell?'' This cannot help us fix a bug, so it is basically useless. We
3543 respond by asking for enough details to enable us to investigate.
3544 You might as well expedite matters by sending them to begin with.
3546 To enable us to fix the bug, you should include all these things:
3550 The version of the utility. Each utility announces it if you start it
3551 with the @option{--version} argument.
3553 Without this, we will not know whether there is any point in looking for
3554 the bug in the current version of the binary utilities.
3557 Any patches you may have applied to the source, including any patches
3558 made to the @code{BFD} library.
3561 The type of machine you are using, and the operating system name and
3565 What compiler (and its version) was used to compile the utilities---e.g.
3569 The command arguments you gave the utility to observe the bug. To
3570 guarantee you will not omit something important, list them all. A copy
3571 of the Makefile (or the output from make) is sufficient.
3573 If we were to try to guess the arguments, we would probably guess wrong
3574 and then we might not encounter the bug.
3577 A complete input file, or set of input files, that will reproduce the
3578 bug. If the utility is reading an object file or files, then it is
3579 generally most helpful to send the actual object files, uuencoded if
3580 necessary to get them through the mail system. Note that
3581 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3582 sending very large files to it. Making the files available for
3583 anonymous FTP is OK.
3585 If the source files were produced exclusively using @sc{gnu} programs
3586 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3587 may be OK to send the source files rather than the object files. In
3588 this case, be sure to say exactly what version of @command{gcc}, or
3589 whatever, was used to produce the object files. Also say how
3590 @command{gcc}, or whatever, was configured.
3593 A description of what behavior you observe that you believe is
3594 incorrect. For example, ``It gets a fatal signal.''
3596 Of course, if the bug is that the utility gets a fatal signal, then we
3597 will certainly notice it. But if the bug is incorrect output, we might
3598 not notice unless it is glaringly wrong. You might as well not give us
3599 a chance to make a mistake.
3601 Even if the problem you experience is a fatal signal, you should still
3602 say so explicitly. Suppose something strange is going on, such as your
3603 copy of the utility is out of synch, or you have encountered a bug in
3604 the C library on your system. (This has happened!) Your copy might
3605 crash and ours would not. If you told us to expect a crash, then when
3606 ours fails to crash, we would know that the bug was not happening for
3607 us. If you had not told us to expect a crash, then we would not be able
3608 to draw any conclusion from our observations.
3611 If you wish to suggest changes to the source, send us context diffs, as
3612 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3613 option. Always send diffs from the old file to the new file. If you
3614 wish to discuss something in the @command{ld} source, refer to it by
3615 context, not by line number.
3617 The line numbers in our development sources will not match those in your
3618 sources. Your line numbers would convey no useful information to us.
3621 Here are some things that are not necessary:
3625 A description of the envelope of the bug.
3627 Often people who encounter a bug spend a lot of time investigating
3628 which changes to the input file will make the bug go away and which
3629 changes will not affect it.
3631 This is often time consuming and not very useful, because the way we
3632 will find the bug is by running a single example under the debugger
3633 with breakpoints, not by pure deduction from a series of examples.
3634 We recommend that you save your time for something else.
3636 Of course, if you can find a simpler example to report @emph{instead}
3637 of the original one, that is a convenience for us. Errors in the
3638 output will be easier to spot, running under the debugger will take
3639 less time, and so on.
3641 However, simplification is not vital; if you do not want to do this,
3642 report the bug anyway and send us the entire test case you used.
3645 A patch for the bug.
3647 A patch for the bug does help us if it is a good one. But do not omit
3648 the necessary information, such as the test case, on the assumption that
3649 a patch is all we need. We might see problems with your patch and decide
3650 to fix the problem another way, or we might not understand it at all.
3652 Sometimes with programs as complicated as the binary utilities it is
3653 very hard to construct an example that will make the program follow a
3654 certain path through the code. If you do not send us the example, we
3655 will not be able to construct one, so we will not be able to verify that
3658 And if we cannot understand what bug you are trying to fix, or why your
3659 patch should be an improvement, we will not install it. A test case will
3660 help us to understand.
3663 A guess about what the bug is or what it depends on.
3665 Such guesses are usually wrong. Even we cannot guess right about such
3666 things without first using the debugger to find the facts.