1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities.
9 * ar: (binutils)ar. Create, modify, and extract from archives
10 * nm: (binutils)nm. List symbols from object files
11 * objcopy: (binutils)objcopy. Copy and translate object files
12 * objdump: (binutils)objdump. Display information from object files
13 * ranlib: (binutils)ranlib. Generate index to archive contents
14 * readelf: (binutils)readelf. Display the contents of ELF format files.
15 * size: (binutils)size. List section sizes and total size
16 * strings: (binutils)strings. List printable strings from files
17 * strip: (binutils)strip. Discard symbols
18 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
19 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
20 * addr2line: (binutils)addr2line. Convert addresses to file and line
21 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
22 * windres: (binutils)windres. Manipulate Windows resources
23 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
29 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 1999 Free Software Foundation, Inc.
31 Permission is granted to make and distribute verbatim copies of
32 this manual provided the copyright notice and this permission notice
33 are preserved on all copies.
36 Permission is granted to process this file through TeX and print the
37 results, provided the printed document carries a copying permission
38 notice identical to this one except for the removal of this paragraph
39 (this paragraph not being relevant to the printed manual).
43 Permission is granted to copy and distribute modified versions of this
44 manual under the conditions for verbatim copying, provided also that
45 the entire resulting derived work is distributed under the terms of a
46 permission notice identical to this one.
48 Permission is granted to copy and distribute translations of this manual
49 into another language, under the above conditions for modified versions.
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
57 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 1999 Free Software Foundation, Inc.
59 @c This text may be freely distributed under the terms of the GNU
60 @c General Public License.
63 @setchapternewpage odd
64 @settitle @sc{gnu} Binary Utilities
67 @title The @sc{gnu} Binary Utilities
68 @subtitle Version @value{VERSION}
71 @author Roland H. Pesch
72 @author Jeffrey M. Osier
73 @author Cygnus Support
77 {\parskip=0pt \hfill Cygnus Support\par \hfill
78 \TeX{}info \texinfoversion\par }
81 @vskip 0pt plus 1filll
82 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
84 Permission is granted to make and distribute verbatim copies of
85 this manual provided the copyright notice and this permission notice
86 are preserved on all copies.
88 Permission is granted to copy and distribute modified versions of this
89 manual under the conditions for verbatim copying, provided also that
90 the entire resulting derived work is distributed under the terms of a
91 permission notice identical to this one.
93 Permission is granted to copy and distribute translations of this manual
94 into another language, under the above conditions for modified versions.
101 This brief manual contains preliminary documentation for the @sc{gnu} binary
102 utilities (collectively version @value{VERSION}):
107 Create, modify, and extract from archives
110 List symbols from object files
113 Copy and translate object files
116 Display information from object files
119 Generate index to archive contents
122 Display the contents of ELF format files.
125 List file section sizes and total size
128 List printable strings from files
134 Demangle encoded C++ symbols (on MS-DOS, this program is named
138 Convert addresses into file names and line numbers
141 Convert object code into a Netware Loadable Module
144 Manipulate Windows resources
147 Create the files needed to build and use Dynamic Link Libraries
152 * ar:: Create, modify, and extract from archives
153 * nm:: List symbols from object files
154 * objcopy:: Copy and translate object files
155 * objdump:: Display information from object files
156 * ranlib:: Generate index to archive contents
157 * readelf:: Display the contents of ELF format files.
158 * size:: List section sizes and total size
159 * strings:: List printable strings from files
160 * strip:: Discard symbols
161 * c++filt:: Filter to demangle encoded C++ symbols
162 * cxxfilt: c++filt. MS-DOS name for c++filt
163 * addr2line:: Convert addresses to file and line
164 * nlmconv:: Converts object code into an NLM
165 * windres:: Manipulate Windows resources
166 * dlltool:: Create files needed to build and use DLLs
167 * Selecting The Target System:: How these utilities determine the target.
168 * Reporting Bugs:: Reporting Bugs
177 @cindex collections of files
179 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
180 ar -M [ <mri-script ]
183 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
193 @sc{gnu} @code{ar} can maintain archives whose members have names of any
194 length; however, depending on how @code{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
201 @code{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @code{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @code{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @code{ar} called
216 @code{ranlib} can be used to add just the table.
218 @cindex compatibility, @code{ar}
219 @cindex @code{ar} compatibility
220 @sc{gnu} @code{ar} is designed to be compatible with two different
221 facilities. You can control its activity using command-line options,
222 like the different varieties of @code{ar} on Unix systems; or, if you
223 specify the single command-line option @samp{-M}, you can control it
224 with a script supplied via standard input, like the MRI ``librarian''
228 * ar cmdline:: Controlling @code{ar} on the command line
229 * ar scripts:: Controlling @code{ar} with a script
234 @section Controlling @code{ar} on the command line
237 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
240 @cindex Unix compatibility, @code{ar}
241 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
242 arguments to execute: one keyletter specifying the @emph{operation}
243 (optionally accompanied by other keyletters specifying
244 @emph{modifiers}), and the archive name to act on.
246 Most operations can also accept further @var{member} arguments,
247 specifying particular files to operate on.
249 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
250 flags @var{mod} in any order, within the first command-line argument.
252 If you wish, you may begin the first command-line argument with a
255 @cindex operations on archive
256 The @var{p} keyletter specifies what operation to execute; it may be
257 any of the following, but you must specify only one of them:
261 @cindex deleting from archive
262 @emph{Delete} modules from the archive. Specify the names of modules to
263 be deleted as @var{member}@dots{}; the archive is untouched if you
264 specify no files to delete.
266 If you specify the @samp{v} modifier, @code{ar} lists each module
270 @cindex moving in archive
271 Use this operation to @emph{move} members in an archive.
273 The ordering of members in an archive can make a difference in how
274 programs are linked using the library, if a symbol is defined in more
277 If no modifiers are used with @code{m}, any members you name in the
278 @var{member} arguments are moved to the @emph{end} of the archive;
279 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
280 specified place instead.
283 @cindex printing from archive
284 @emph{Print} the specified members of the archive, to the standard
285 output file. If the @samp{v} modifier is specified, show the member
286 name before copying its contents to standard output.
288 If you specify no @var{member} arguments, all the files in the archive are
292 @cindex quick append to archive
293 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
294 @var{archive}, without checking for replacement.
296 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
297 operation; new members are always placed at the end of the archive.
299 The modifier @samp{v} makes @code{ar} list each file as it is appended.
301 Since the point of this operation is speed, the archive's symbol table
302 index is not updated, even if it already existed; you can use @samp{ar s} or
303 @code{ranlib} explicitly to update the symbol table index.
305 However, too many different systems assume quick append rebuilds the
306 index, so GNU ar implements @code{q} as a synonym for @code{r}.
309 @cindex replacement in archive
310 Insert the files @var{member}@dots{} into @var{archive} (with
311 @emph{replacement}). This operation differs from @samp{q} in that any
312 previously existing members are deleted if their names match those being
315 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
316 displays an error message, and leaves undisturbed any existing members
317 of the archive matching that name.
319 By default, new members are added at the end of the file; but you may
320 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
321 placement relative to some existing member.
323 The modifier @samp{v} used with this operation elicits a line of
324 output for each file inserted, along with one of the letters @samp{a} or
325 @samp{r} to indicate whether the file was appended (no old member
326 deleted) or replaced.
329 @cindex contents of archive
330 Display a @emph{table} listing the contents of @var{archive}, or those
331 of the files listed in @var{member}@dots{} that are present in the
332 archive. Normally only the member name is shown; if you also want to
333 see the modes (permissions), timestamp, owner, group, and size, you can
334 request that by also specifying the @samp{v} modifier.
336 If you do not specify a @var{member}, all files in the archive
339 @cindex repeated names in archive
340 @cindex name duplication in archive
341 If there is more than one file with the same name (say, @samp{fie}) in
342 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
343 first instance; to see them all, you must ask for a complete
344 listing---in our example, @samp{ar t b.a}.
345 @c WRS only; per Gumby, this is implementation-dependent, and in a more
346 @c recent case in fact works the other way.
349 @cindex extract from archive
350 @emph{Extract} members (named @var{member}) from the archive. You can
351 use the @samp{v} modifier with this operation, to request that
352 @code{ar} list each name as it extracts it.
354 If you do not specify a @var{member}, all files in the archive
359 A number of modifiers (@var{mod}) may immediately follow the @var{p}
360 keyletter, to specify variations on an operation's behavior:
364 @cindex relative placement in archive
365 Add new files @emph{after} an existing member of the
366 archive. If you use the modifier @samp{a}, the name of an existing archive
367 member must be present as the @var{relpos} argument, before the
368 @var{archive} specification.
371 Add new files @emph{before} an existing member of the
372 archive. If you use the modifier @samp{b}, the name of an existing archive
373 member must be present as the @var{relpos} argument, before the
374 @var{archive} specification. (same as @samp{i}).
377 @cindex creating archives
378 @emph{Create} the archive. The specified @var{archive} is always
379 created if it did not exist, when you request an update. But a warning is
380 issued unless you specify in advance that you expect to create it, by
384 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
385 names of any length. This will cause it to create archives which are
386 not compatible with the native @code{ar} program on some systems. If
387 this is a concern, the @samp{f} modifier may be used to truncate file
388 names when putting them in the archive.
391 Insert new files @emph{before} an existing member of the
392 archive. If you use the modifier @samp{i}, the name of an existing archive
393 member must be present as the @var{relpos} argument, before the
394 @var{archive} specification. (same as @samp{b}).
397 This modifier is accepted but not used.
398 @c whaffor ar l modifier??? presumably compat; with
399 @c what???---doc@@cygnus.com, 25jan91
402 Uses the @var{count} parameter. This is used if there are multiple
403 entries in the archive with the same name. Extract or delete instance
404 @var{count} of the given name from the archive.
407 @cindex dates in archive
408 Preserve the @emph{original} dates of members when extracting them. If
409 you do not specify this modifier, files extracted from the archive
410 are stamped with the time of extraction.
413 Use the full path name when matching names in the archive. @sc{gnu}
414 @code{ar} can not create an archive with a full path name (such archives
415 are not POSIX complaint), but other archive creators can. This option
416 will cause @sc{gnu} @code{ar} to match file names using a complete path
417 name, which can be convenient when extracting a single file from an
418 archive created by another tool.
421 @cindex writing archive index
422 Write an object-file index into the archive, or update an existing one,
423 even if no other change is made to the archive. You may use this modifier
424 flag either with any operation, or alone. Running @samp{ar s} on an
425 archive is equivalent to running @samp{ranlib} on it.
428 @cindex not writing archive index
429 Do not generate an archive symbol table. This can speed up building a
430 large library in several steps. The resulting archive can not be used
431 with the linker. In order to build a symbol table, you must omit the
432 @samp{S} modifier on the last execution of @samp{ar}, or you must run
433 @samp{ranlib} on the archive.
436 @cindex updating an archive
437 Normally, @samp{ar r}@dots{} inserts all files
438 listed into the archive. If you would like to insert @emph{only} those
439 of the files you list that are newer than existing members of the same
440 names, use this modifier. The @samp{u} modifier is allowed only for the
441 operation @samp{r} (replace). In particular, the combination @samp{qu} is
442 not allowed, since checking the timestamps would lose any speed
443 advantage from the operation @samp{q}.
446 This modifier requests the @emph{verbose} version of an operation. Many
447 operations display additional information, such as filenames processed,
448 when the modifier @samp{v} is appended.
451 This modifier shows the version number of @code{ar}.
455 @section Controlling @code{ar} with a script
458 ar -M [ <@var{script} ]
461 @cindex MRI compatibility, @code{ar}
462 @cindex scripts, @code{ar}
463 If you use the single command-line option @samp{-M} with @code{ar}, you
464 can control its operation with a rudimentary command language. This
465 form of @code{ar} operates interactively if standard input is coming
466 directly from a terminal. During interactive use, @code{ar} prompts for
467 input (the prompt is @samp{AR >}), and continues executing even after
468 errors. If you redirect standard input to a script file, no prompts are
469 issued, and @code{ar} abandons execution (with a nonzero exit code)
472 The @code{ar} command language is @emph{not} designed to be equivalent
473 to the command-line options; in fact, it provides somewhat less control
474 over archives. The only purpose of the command language is to ease the
475 transition to @sc{gnu} @code{ar} for developers who already have scripts
476 written for the MRI ``librarian'' program.
478 The syntax for the @code{ar} command language is straightforward:
481 commands are recognized in upper or lower case; for example, @code{LIST}
482 is the same as @code{list}. In the following descriptions, commands are
483 shown in upper case for clarity.
486 a single command may appear on each line; it is the first word on the
490 empty lines are allowed, and have no effect.
493 comments are allowed; text after either of the characters @samp{*}
494 or @samp{;} is ignored.
497 Whenever you use a list of names as part of the argument to an @code{ar}
498 command, you can separate the individual names with either commas or
499 blanks. Commas are shown in the explanations below, for clarity.
502 @samp{+} is used as a line continuation character; if @samp{+} appears
503 at the end of a line, the text on the following line is considered part
504 of the current command.
507 Here are the commands you can use in @code{ar} scripts, or when using
508 @code{ar} interactively. Three of them have special significance:
510 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
511 a temporary file required for most of the other commands.
513 @code{SAVE} commits the changes so far specified by the script. Prior
514 to @code{SAVE}, commands affect only the temporary copy of the current
518 @item ADDLIB @var{archive}
519 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
520 Add all the contents of @var{archive} (or, if specified, each named
521 @var{module} from @var{archive}) to the current archive.
523 Requires prior use of @code{OPEN} or @code{CREATE}.
525 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
526 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
527 @c else like "ar q..."
528 Add each named @var{member} as a module in the current archive.
530 Requires prior use of @code{OPEN} or @code{CREATE}.
533 Discard the contents of the current archive, canceling the effect of
534 any operations since the last @code{SAVE}. May be executed (with no
535 effect) even if no current archive is specified.
537 @item CREATE @var{archive}
538 Creates an archive, and makes it the current archive (required for many
539 other commands). The new archive is created with a temporary name; it
540 is not actually saved as @var{archive} until you use @code{SAVE}.
541 You can overwrite existing archives; similarly, the contents of any
542 existing file named @var{archive} will not be destroyed until @code{SAVE}.
544 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
545 Delete each listed @var{module} from the current archive; equivalent to
546 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
548 Requires prior use of @code{OPEN} or @code{CREATE}.
550 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
551 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
552 List each named @var{module} present in @var{archive}. The separate
553 command @code{VERBOSE} specifies the form of the output: when verbose
554 output is off, output is like that of @samp{ar -t @var{archive}
555 @var{module}@dots{}}. When verbose output is on, the listing is like
556 @samp{ar -tv @var{archive} @var{module}@dots{}}.
558 Output normally goes to the standard output stream; however, if you
559 specify @var{outputfile} as a final argument, @code{ar} directs the
563 Exit from @code{ar}, with a @code{0} exit code to indicate successful
564 completion. This command does not save the output file; if you have
565 changed the current archive since the last @code{SAVE} command, those
568 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
569 Extract each named @var{module} from the current archive, writing them
570 into the current directory as separate files. Equivalent to @samp{ar -x
571 @var{archive} @var{module}@dots{}}.
573 Requires prior use of @code{OPEN} or @code{CREATE}.
576 @c FIXME Tokens but no commands???
583 Display full contents of the current archive, in ``verbose'' style
584 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
585 tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
586 enhancement, rather than present for MRI compatibility.)
588 Requires prior use of @code{OPEN} or @code{CREATE}.
590 @item OPEN @var{archive}
591 Opens an existing archive for use as the current archive (required for
592 many other commands). Any changes as the result of subsequent commands
593 will not actually affect @var{archive} until you next use @code{SAVE}.
595 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
596 In the current archive, replace each existing @var{module} (named in
597 the @code{REPLACE} arguments) from files in the current working directory.
598 To execute this command without errors, both the file, and the module in
599 the current archive, must exist.
601 Requires prior use of @code{OPEN} or @code{CREATE}.
604 Toggle an internal flag governing the output from @code{DIRECTORY}.
605 When the flag is on, @code{DIRECTORY} output matches output from
606 @samp{ar -tv }@dots{}.
609 Commit your changes to the current archive, and actually save it as a
610 file with the name specified in the last @code{CREATE} or @code{OPEN}
613 Requires prior use of @code{OPEN} or @code{CREATE}.
622 The @sc{gnu} linker @code{ld} is now described in a separate manual.
623 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
632 nm [ -a | --debug-syms ] [ -g | --extern-only ]
633 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
634 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
635 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
636 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
637 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
638 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
639 [ --defined-only ] [-l | --line-numbers ]
640 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
643 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
644 If no object files are listed as arguments, @code{nm} assumes the file
647 For each symbol, @code{nm} shows:
651 The symbol value, in the radix selected by options (see below), or
652 hexadecimal by default.
655 The symbol type. At least the following types are used; others are, as
656 well, depending on the object file format. If lowercase, the symbol is
657 local; if uppercase, the symbol is global (external).
659 @c Some more detail on exactly what these symbol types are used for
663 The symbol's value is absolute, and will not be changed by further
667 The symbol is in the uninitialized data section (known as BSS).
670 The symbol is common. Common symbols are uninitialized data. When
671 linking, multiple common symbols may appear with the same name. If the
672 symbol is defined anywhere, the common symbols are treated as undefined
673 references. For more details on common symbols, see the discussion of
674 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
677 The symbol is in the initialized data section.
680 The symbol is in an initialized data section for small objects. Some
681 object file formats permit more efficient access to small data objects,
682 such as a global int variable as opposed to a large global array.
685 The symbol is an indirect reference to another symbol. This is a GNU
686 extension to the a.out object file format which is rarely used.
689 The symbol is a debugging symbol.
692 The symbol is in a read only data section.
695 The symbol is in an uninitialized data section for small objects.
698 The symbol is in the text (code) section.
701 The symbol is undefined.
704 The symbol is weak. When a weak defined symbol is linked with a normal
705 defined symbol, the normal defined symbol is used with no error. When a
706 weak undefined symbol is linked and the symbol is not defined, the value
707 of the weak symbol becomes zero with no error.
710 The symbol is a stabs symbol in an a.out object file. In this case, the
711 next values printed are the stabs other field, the stabs desc field, and
712 the stab type. Stabs symbols are used to hold debugging information;
713 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
714 ``stabs'' debug format}.
717 The symbol type is unknown, or object file format specific.
724 The long and short forms of options, shown here as alternatives, are
730 @itemx --print-file-name
731 @cindex input file name
733 @cindex source file name
734 Precede each symbol by the name of the input file (or archive member)
735 in which it was found, rather than identifying the input file once only,
736 before all of its symbols.
740 @cindex debugging symbols
741 Display all symbols, even debugger-only symbols; normally these are not
745 @cindex @code{nm} format
746 @cindex @code{nm} compatibility
747 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
751 @cindex demangling in nm
752 Decode (@dfn{demangle}) low-level symbol names into user-level names.
753 Besides removing any initial underscore prepended by the system, this
754 makes C++ function names readable. @xref{c++filt}, for more information
758 Do not demangle low-level symbol names. This is the default.
762 @cindex dynamic symbols
763 Display the dynamic symbols rather than the normal symbols. This is
764 only meaningful for dynamic objects, such as certain types of shared
767 @item -f @var{format}
768 @itemx --format=@var{format}
769 @cindex @code{nm} format
770 @cindex @code{nm} compatibility
771 Use the output format @var{format}, which can be @code{bsd},
772 @code{sysv}, or @code{posix}. The default is @code{bsd}.
773 Only the first character of @var{format} is significant; it can be
774 either upper or lower case.
778 @cindex external symbols
779 Display only external symbols.
782 @itemx --line-numbers
783 @cindex symbol line numbers
784 For each symbol, use debugging information to try to find a filename and
785 line number. For a defined symbol, look for the line number of the
786 address of the symbol. For an undefined symbol, look for the line
787 number of a relocation entry which refers to the symbol. If line number
788 information can be found, print it after the other symbol information.
792 @itemx --numeric-sort
793 Sort symbols numerically by their addresses, rather than alphabetically
798 @cindex sorting symbols
799 Do not bother to sort the symbols in any order; print them in the order
804 Use the POSIX.2 standard output format instead of the default format.
805 Equivalent to @samp{-f posix}.
809 @cindex symbol index, listing
810 When listing symbols from archive members, include the index: a mapping
811 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
812 contain definitions for which names.
815 @itemx --reverse-sort
816 Reverse the order of the sort (whether numeric or alphabetic); let the
820 Sort symbols by size. The size is computed as the difference between
821 the value of the symbol and the value of the symbol with the next higher
822 value. The size of the symbol is printed, rather than the value.
825 @itemx --radix=@var{radix}
826 Use @var{radix} as the radix for printing the symbol values. It must be
827 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
829 @item --target=@var{bfdname}
830 @cindex object code format
831 Specify an object code format other than your system's default format.
832 @xref{Target Selection}, for more information.
835 @itemx --undefined-only
836 @cindex external symbols
837 @cindex undefined symbols
838 Display only undefined symbols (those external to each object file).
841 @cindex external symbols
842 @cindex undefined symbols
843 Display only defined symbols for each object file.
847 Show the version number of @code{nm} and exit.
850 Show a summary of the options to @code{nm} and exit.
857 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
858 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
859 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
860 [ -S | --strip-all ] [ -g | --strip-debug ]
861 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
862 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
863 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
864 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
865 [ -x | --discard-all ] [ -X | --discard-locals ]
866 [ -b @var{byte} | --byte=@var{byte} ]
867 [ -i @var{interleave} | --interleave=@var{interleave} ]
868 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
869 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
870 [ -p | --preserve-dates ] [ --debugging ]
871 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
872 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
873 [ --change-addresses=@var{incr} ]
874 [ --change-section-address=@var{section}@{=,+,-@}@var{val} ]
875 [ --change-section-lma=@var{section}@{=,+,-@}@var{val} ]
876 [ --change-section-vma=@var{section}@{=,+,-@}@var{val} ]
877 [ --change-warnings ] [ --no-change-warnings ]
878 [ --set-section-flags=@var{section}=@var{flags} ]
879 [ --add-section=@var{sectionname}=@var{filename} ]
880 [ --change-leading-char ] [ --remove-leading-char ]
882 [ -v | --verbose ] [ -V | --version ] [ --help ]
883 @var{infile} [@var{outfile}]
886 The @sc{gnu} @code{objcopy} utility copies the contents of an object
887 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
888 read and write the object files. It can write the destination object
889 file in a format different from that of the source object file. The
890 exact behavior of @code{objcopy} is controlled by command-line options.
892 @code{objcopy} creates temporary files to do its translations and
893 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
894 translation work; it has access to all the formats described in @sc{bfd}
895 and thus is able to recognize most formats without being told
896 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
898 @code{objcopy} can be used to generate S-records by using an output
899 target of @samp{srec} (e.g., use @samp{-O srec}).
901 @code{objcopy} can be used to generate a raw binary file by using an
902 output target of @samp{binary} (e.g., use @samp{-O binary}). When
903 @code{objcopy} generates a raw binary file, it will essentially produce
904 a memory dump of the contents of the input object file. All symbols and
905 relocation information will be discarded. The memory dump will start at
906 the load address of the lowest section copied into the output file.
908 When generating an S-record or a raw binary file, it may be helpful to
909 use @samp{-S} to remove sections containing debugging information. In
910 some cases @samp{-R} will be useful to remove sections which contain
911 information that is not needed by the binary file.
916 The input and output files, respectively.
917 If you do not specify @var{outfile}, @code{objcopy} creates a
918 temporary file and destructively renames the result with
919 the name of @var{infile}.
921 @item -I @var{bfdname}
922 @itemx --input-target=@var{bfdname}
923 Consider the source file's object format to be @var{bfdname}, rather than
924 attempting to deduce it. @xref{Target Selection}, for more information.
926 @item -O @var{bfdname}
927 @itemx --output-target=@var{bfdname}
928 Write the output file using the object format @var{bfdname}.
929 @xref{Target Selection}, for more information.
931 @item -F @var{bfdname}
932 @itemx --target=@var{bfdname}
933 Use @var{bfdname} as the object format for both the input and the output
934 file; i.e., simply transfer data from source to destination with no
935 translation. @xref{Target Selection}, for more information.
937 @item -j @var{sectionname}
938 @itemx --only-section=@var{sectionname}
939 Copy only the named section from the input file to the output file.
940 This option may be given more than once. Note that using this option
941 inappropriately may make the output file unusable.
943 @item -R @var{sectionname}
944 @itemx --remove-section=@var{sectionname}
945 Remove any section named @var{sectionname} from the output file. This
946 option may be given more than once. Note that using this option
947 inappropriately may make the output file unusable.
951 Do not copy relocation and symbol information from the source file.
955 Do not copy debugging symbols from the source file.
957 @item --strip-unneeded
958 Strip all symbols that are not needed for relocation processing.
960 @item -K @var{symbolname}
961 @itemx --keep-symbol=@var{symbolname}
962 Copy only symbol @var{symbolname} from the source file. This option may
963 be given more than once.
965 @item -N @var{symbolname}
966 @itemx --strip-symbol=@var{symbolname}
967 Do not copy symbol @var{symbolname} from the source file. This option
968 may be given more than once.
970 @item -L @var{symbolname}
971 @itemx --localize-symbol=@var{symbolname}
972 Make symbol @var{symbolname} local to the file, so that it is not
973 visible externally. This option may be given more than once.
975 @item -W @var{symbolname}
976 @itemx --weaken-symbol=@var{symbolname}
977 Make symbol @var{symbolname} weak. This option may be given more than once.
981 Do not copy non-global symbols from the source file.
982 @c FIXME any reason to prefer "non-global" to "local" here?
985 @itemx --discard-locals
986 Do not copy compiler-generated local symbols.
987 (These usually start with @samp{L} or @samp{.}.)
990 @itemx --byte=@var{byte}
991 Keep only every @var{byte}th byte of the input file (header data is not
992 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
993 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
994 option, or the default of 4. This option is useful for creating files
995 to program @sc{rom}. It is typically used with an @code{srec} output
998 @item -i @var{interleave}
999 @itemx --interleave=@var{interleave}
1000 Only copy one out of every @var{interleave} bytes. Select which byte to
1001 copy with the @var{-b} or @samp{--byte} option. The default is 4.
1002 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
1006 @itemx --preserve-dates
1007 Set the access and modification dates of the output file to be the same
1008 as those of the input file.
1011 Convert debugging information, if possible. This is not the default
1012 because only certain debugging formats are supported, and the
1013 conversion process can be time consuming.
1015 @item --gap-fill @var{val}
1016 Fill gaps between sections with @var{val}. This operation applies to
1017 the @emph{load address} (LMA) of the sections. It is done by increasing
1018 the size of the section with the lower address, and filling in the extra
1019 space created with @var{val}.
1021 @item --pad-to @var{address}
1022 Pad the output file up to the load address @var{address}. This is
1023 done by increasing the size of the last section. The extra space is
1024 filled in with the value specified by @samp{--gap-fill} (default zero).
1026 @item --set-start @var{val}
1027 Set the start address of the new file to @var{val}. Not all object file
1028 formats support setting the start address.
1030 @item --change-start @var{incr}
1031 @itemx --adjust-start @var{incr}
1032 @cindex changing start address
1033 Change the start address by adding @var{incr}. Not all object file
1034 formats support setting the start address.
1036 @item --change-addresses @var{incr}
1037 @itemx --adjust-vma @var{incr}
1038 @cindex changing object addresses
1039 Change the VMA and LMA addresses of all sections, as well as the start
1040 address, by adding @var{incr}. Some object file formats do not permit
1041 section addresses to be changed arbitrarily. Note that this does not
1042 relocate the sections; if the program expects sections to be loaded at a
1043 certain address, and this option is used to change the sections such
1044 that they are loaded at a different address, the program may fail.
1046 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1047 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1048 @cindex changing section address
1049 Set or change both the VMA address and the LMA address of the named
1050 @var{section}. If @samp{=} is used, the section address is set to
1051 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1052 section address. See the comments under @samp{--change-addresses},
1053 above. If @var{section} does not exist in the input file, a warning will
1054 be issued, unless @samp{--no-change-warnings} is used.
1056 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1057 @cindex changing section LMA
1058 Set or change the LMA address of the named @var{section}. The LMA
1059 address is the address where the section will be loaded into memory at
1060 program load time. Normally this is the same as the VMA address, which
1061 is the address of the section at program run time, but on some systems,
1062 especially those where a program is held in ROM, the two can be
1063 different. If @samp{=} is used, the section address is set to
1064 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1065 section address. See the comments under @samp{--change-addresses},
1066 above. If @var{section} does not exist in the input file, a warning
1067 will be issued, unless @samp{--no-change-warnings} is used.
1069 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1070 @cindex changing section VMA
1071 Set or change the VMA address of the named @var{section}. The VMA
1072 address is the address where the section will be located once the
1073 program has started executing. Normally this is the same as the LMA
1074 address, which is the address where the section will be loaded into
1075 memory, but on some systems, especially those where a program is held in
1076 ROM, the two can be different. If @samp{=} is used, the section address
1077 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1078 from the section address. See the comments under
1079 @samp{--change-addresses}, above. If @var{section} does not exist in
1080 the input file, a warning will be issued, unless
1081 @samp{--no-change-warnings} is used.
1083 @item --change-warnings
1084 @itemx --adjust-warnings
1085 If @samp{--change-section-address} or @samp{--change-section-lma} or
1086 @samp{--change-section-vma} is used, and the named section does not
1087 exist, issue a warning. This is the default.
1089 @item --no-change-warnings
1090 @itemx --no-adjust-warnings
1091 Do not issue a warning if @samp{--change-section-address} or
1092 @samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1093 if the named section does not exist.
1095 @item --set-section-flags @var{section}=@var{flags}
1096 Set the flags for the named section. The @var{flags} argument is a
1097 comma separated string of flag names. The recognized names are
1098 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1099 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1100 @samp{debug}. You can set the @samp{contents} flag for a section which
1101 does not have contents, but it is not meaningful to clear the
1102 @samp{contents} flag of a section which does have contents--just remove
1103 the section instead. Not all flags are meaningful for all object file
1106 @item --add-section @var{sectionname}=@var{filename}
1107 Add a new section named @var{sectionname} while copying the file. The
1108 contents of the new section are taken from the file @var{filename}. The
1109 size of the section will be the size of the file. This option only
1110 works on file formats which can support sections with arbitrary names.
1112 @item --change-leading-char
1113 Some object file formats use special characters at the start of
1114 symbols. The most common such character is underscore, which compilers
1115 often add before every symbol. This option tells @code{objcopy} to
1116 change the leading character of every symbol when it converts between
1117 object file formats. If the object file formats use the same leading
1118 character, this option has no effect. Otherwise, it will add a
1119 character, or remove a character, or change a character, as
1122 @item --remove-leading-char
1123 If the first character of a global symbol is a special symbol leading
1124 character used by the object file format, remove the character. The
1125 most common symbol leading character is underscore. This option will
1126 remove a leading underscore from all global symbols. This can be useful
1127 if you want to link together objects of different file formats with
1128 different conventions for symbol names. This is different from
1129 @code{--change-leading-char} because it always changes the symbol name
1130 when appropriate, regardless of the object file format of the output
1134 Change all global symbols in the file to be weak. This can be useful
1135 when building an object which will be linked against other objects using
1136 the @code{-R} option to the linker. This option is only effective when
1137 using an object file format which supports weak symbols.
1141 Show the version number of @code{objcopy}.
1145 Verbose output: list all object files modified. In the case of
1146 archives, @samp{objcopy -V} lists all members of the archive.
1149 Show a summary of the options to @code{objcopy}.
1155 @cindex object file information
1159 objdump [ -a | --archive-headers ]
1160 [ -b @var{bfdname} | --target=@var{bfdname} ] [ --debugging ]
1161 [ -C | --demangle ] [ -d | --disassemble ]
1162 [ -D | --disassemble-all ] [ --disassemble-zeroes ]
1163 [ -EB | -EL | --endian=@{big | little @} ]
1164 [ -f | --file-headers ]
1165 [ -h | --section-headers | --headers ] [ -i | --info ]
1166 [ -j @var{section} | --section=@var{section} ]
1167 [ -l | --line-numbers ] [ -S | --source ]
1168 [ -m @var{machine} | --architecture=@var{machine} ]
1169 [ -M @var{options} | --disassembler-options=@var{options}]
1170 [ -p | --private-headers ]
1171 [ -r | --reloc ] [ -R | --dynamic-reloc ]
1172 [ -s | --full-contents ] [ --stabs ]
1173 [ -t | --syms ] [ -T | --dynamic-syms ] [ -x | --all-headers ]
1174 [ -w | --wide ] [ --start-address=@var{address} ]
1175 [ --stop-address=@var{address} ]
1176 [ --prefix-addresses] [ --[no-]show-raw-insn ]
1177 [ --adjust-vma=@var{offset} ]
1178 [ --version ] [ --help ]
1179 @var{objfile}@dots{}
1182 @code{objdump} displays information about one or more object files.
1183 The options control what particular information to display. This
1184 information is mostly useful to programmers who are working on the
1185 compilation tools, as opposed to programmers who just want their
1186 program to compile and work.
1188 @var{objfile}@dots{} are the object files to be examined. When you
1189 specify archives, @code{objdump} shows information on each of the member
1192 The long and short forms of options, shown here as alternatives, are
1193 equivalent. At least one option besides @samp{-l} must be given.
1197 @itemx --archive-header
1198 @cindex archive headers
1199 If any of the @var{objfile} files are archives, display the archive
1200 header information (in a format similar to @samp{ls -l}). Besides the
1201 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1202 the object file format of each archive member.
1204 @item --adjust-vma=@var{offset}
1205 @cindex section addresses in objdump
1206 @cindex VMA in objdump
1207 When dumping information, first add @var{offset} to all the section
1208 addresses. This is useful if the section addresses do not correspond to
1209 the symbol table, which can happen when putting sections at particular
1210 addresses when using a format which can not represent section addresses,
1213 @item -b @var{bfdname}
1214 @itemx --target=@var{bfdname}
1215 @cindex object code format
1216 Specify that the object-code format for the object files is
1217 @var{bfdname}. This option may not be necessary; @var{objdump} can
1218 automatically recognize many formats.
1222 objdump -b oasys -m vax -h fu.o
1225 displays summary information from the section headers (@samp{-h}) of
1226 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1227 file in the format produced by Oasys compilers. You can list the
1228 formats available with the @samp{-i} option.
1229 @xref{Target Selection}, for more information.
1233 @cindex demangling in objdump
1234 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1235 Besides removing any initial underscore prepended by the system, this
1236 makes C++ function names readable. @xref{c++filt}, for more information
1240 Display debugging information. This attempts to parse debugging
1241 information stored in the file and print it out using a C like syntax.
1242 Only certain types of debugging information have been implemented.
1245 @itemx --disassemble
1246 @cindex disassembling object code
1247 @cindex machine instructions
1248 Display the assembler mnemonics for the machine instructions from
1249 @var{objfile}. This option only disassembles those sections which are
1250 expected to contain instructions.
1253 @itemx --disassemble-all
1254 Like @samp{-d}, but disassemble the contents of all sections, not just
1255 those expected to contain instructions.
1257 @item --prefix-addresses
1258 When disassembling, print the complete address on each line. This is
1259 the older disassembly format.
1261 @item --disassemble-zeroes
1262 Normally the disassembly output will skip blocks of zeroes. This
1263 option directs the disassembler to disassemble those blocks, just like
1268 @itemx --endian=@{big|little@}
1270 @cindex disassembly endianness
1271 Specify the endianness of the object files. This only affects
1272 disassembly. This can be useful when disassembling a file format which
1273 does not describe endianness information, such as S-records.
1276 @itemx --file-header
1277 @cindex object file header
1278 Display summary information from the overall header of
1279 each of the @var{objfile} files.
1282 @itemx --section-header
1284 @cindex section headers
1285 Display summary information from the section headers of the
1288 File segments may be relocated to nonstandard addresses, for example by
1289 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1290 @code{ld}. However, some object file formats, such as a.out, do not
1291 store the starting address of the file segments. In those situations,
1292 although @code{ld} relocates the sections correctly, using @samp{objdump
1293 -h} to list the file section headers cannot show the correct addresses.
1294 Instead, it shows the usual addresses, which are implicit for the
1298 Print a summary of the options to @code{objdump} and exit.
1302 @cindex architectures available
1303 @cindex object formats available
1304 Display a list showing all architectures and object formats available
1305 for specification with @samp{-b} or @samp{-m}.
1308 @itemx --section=@var{name}
1309 @cindex section information
1310 Display information only for section @var{name}.
1313 @itemx --line-numbers
1314 @cindex source filenames for object files
1315 Label the display (using debugging information) with the filename and
1316 source line numbers corresponding to the object code or relocs shown.
1317 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1319 @item -m @var{machine}
1320 @itemx --architecture=@var{machine}
1321 @cindex architecture
1322 @cindex disassembly architecture
1323 Specify the architecture to use when disassembling object files. This
1324 can be useful when disassembling object files which do not describe
1325 architecture information, such as S-records. You can list the available
1326 architectures with the @samp{-i} option.
1328 @item -M @var{options}
1329 @itemx --disassembler-options=@var{options}
1330 Pass target specific information to the disassembler. Only supported on
1333 If the target is an ARM architecture then this switch can be used to
1334 select which register name set is used during disassembler. Specifying
1335 @samp{--disassembler-options=reg-name-std} (the default) will select the
1336 register names as used in ARM's instruction set documentation, but with
1337 register 13 called 'sp', register 14 called 'lr' and register 15 called
1338 'pc'. Specifying @samp{--disassembler-options=reg-names-apcs} will
1339 select the name set used by the ARM Procedure Call Standard, whilst
1340 specifying @samp{--disassembler-options=reg-names-raw} will just use
1341 @samp{r} followed by the register number.
1344 @itemx --private-headers
1345 Print information that is specific to the object file format. The exact
1346 information printed depends upon the object file format. For some
1347 object file formats, no additional information is printed.
1351 @cindex relocation entries, in object file
1352 Print the relocation entries of the file. If used with @samp{-d} or
1353 @samp{-D}, the relocations are printed interspersed with the
1357 @itemx --dynamic-reloc
1358 @cindex dynamic relocation entries, in object file
1359 Print the dynamic relocation entries of the file. This is only
1360 meaningful for dynamic objects, such as certain types of shared
1364 @itemx --full-contents
1365 @cindex sections, full contents
1366 @cindex object file sections
1367 Display the full contents of any sections requested.
1371 @cindex source disassembly
1372 @cindex disassembly, with source
1373 Display source code intermixed with disassembly, if possible. Implies
1376 @item --show-raw-insn
1377 When disassembling instructions, print the instruction in hex as well as
1378 in symbolic form. This is the default except when
1379 @code{--prefix-addresses} is used.
1381 @item --no-show-raw-insn
1382 When disassembling instructions, do not print the instruction bytes.
1383 This is the default when @code{--prefix-addresses} is used.
1388 @cindex debug symbols
1389 @cindex ELF object file format
1390 Display the full contents of any sections requested. Display the
1391 contents of the .stab and .stab.index and .stab.excl sections from an
1392 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1393 @code{.stab} debugging symbol-table entries are carried in an ELF
1394 section. In most other file formats, debugging symbol-table entries are
1395 interleaved with linkage symbols, and are visible in the @samp{--syms}
1396 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1397 Overview,stabs.info, The ``stabs'' debug format}.
1399 @item --start-address=@var{address}
1400 @cindex start-address
1401 Start displaying data at the specified address. This affects the output
1402 of the @code{-d}, @code{-r} and @code{-s} options.
1404 @item --stop-address=@var{address}
1405 @cindex stop-address
1406 Stop displaying data at the specified address. This affects the output
1407 of the @code{-d}, @code{-r} and @code{-s} options.
1411 @cindex symbol table entries, printing
1412 Print the symbol table entries of the file.
1413 This is similar to the information provided by the @samp{nm} program.
1416 @itemx --dynamic-syms
1417 @cindex dynamic symbol table entries, printing
1418 Print the dynamic symbol table entries of the file. This is only
1419 meaningful for dynamic objects, such as certain types of shared
1420 libraries. This is similar to the information provided by the @samp{nm}
1421 program when given the @samp{-D} (@samp{--dynamic}) option.
1424 Print the version number of @code{objdump} and exit.
1428 @cindex all header information, object file
1429 @cindex header information, all
1430 Display all available header information, including the symbol table and
1431 relocation entries. Using @samp{-x} is equivalent to specifying all of
1432 @samp{-a -f -h -r -t}.
1436 @cindex wide output, printing
1437 Format some lines for output devices that have more than 80 columns.
1444 @cindex archive contents
1445 @cindex symbol index
1448 ranlib [-vV] @var{archive}
1451 @code{ranlib} generates an index to the contents of an archive and
1452 stores it in the archive. The index lists each symbol defined by a
1453 member of an archive that is a relocatable object file.
1455 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1457 An archive with such an index speeds up linking to the library and
1458 allows routines in the library to call each other without regard to
1459 their placement in the archive.
1461 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1462 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1469 Show the version number of @code{ranlib}.
1476 @cindex section sizes
1479 size [ -A | -B | --format=@var{compatibility} ]
1480 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1481 [ --target=@var{bfdname} ] [ -V | --version ]
1482 [ @var{objfile}@dots{} ]
1485 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1486 size---for each of the object or archive files @var{objfile} in its
1487 argument list. By default, one line of output is generated for each
1488 object file or each module in an archive.
1490 @var{objfile}@dots{} are the object files to be examined.
1491 If none are specified, the file @code{a.out} will be used.
1493 The command line options have the following meanings:
1498 @itemx --format=@var{compatibility}
1499 @cindex @code{size} display format
1500 Using one of these options, you can choose whether the output from @sc{gnu}
1501 @code{size} resembles output from System V @code{size} (using @samp{-A},
1502 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1503 @samp{--format=berkeley}). The default is the one-line format similar to
1505 @c Bonus for doc-source readers: you can also say --format=strange (or
1506 @c anything else that starts with 's') for sysv, and --format=boring (or
1507 @c anything else that starts with 'b') for Berkeley.
1509 Here is an example of the Berkeley (default) format of output from
1512 $ size --format=Berkeley ranlib size
1513 text data bss dec hex filename
1514 294880 81920 11592 388392 5ed28 ranlib
1515 294880 81920 11888 388688 5ee50 size
1519 This is the same data, but displayed closer to System V conventions:
1522 $ size --format=SysV ranlib size
1540 Show a summary of acceptable arguments and options.
1545 @itemx --radix=@var{number}
1546 @cindex @code{size} number format
1547 @cindex radix for section sizes
1548 Using one of these options, you can control whether the size of each
1549 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1550 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1551 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1552 values (8, 10, 16) are supported. The total size is always given in two
1553 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1554 octal and hexadecimal if you're using @samp{-o}.
1556 @item --target=@var{bfdname}
1557 @cindex object code format
1558 Specify that the object-code format for @var{objfile} is
1559 @var{bfdname}. This option may not be necessary; @code{size} can
1560 automatically recognize many formats.
1561 @xref{Target Selection}, for more information.
1565 Display the version number of @code{size}.
1571 @cindex listings strings
1572 @cindex printing strings
1573 @cindex strings, printing
1576 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1577 [--all] [--print-file-name] [--bytes=@var{min-len}]
1578 [--radix=@var{radix}] [--target=@var{bfdname}]
1579 [--help] [--version] @var{file}@dots{}
1582 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1583 character sequences that are at least 4 characters long (or the number
1584 given with the options below) and are followed by an unprintable
1585 character. By default, it only prints the strings from the initialized
1586 and loaded sections of object files; for other types of files, it prints
1587 the strings from the whole file.
1589 @code{strings} is mainly useful for determining the contents of non-text
1596 Do not scan only the initialized and loaded sections of object files;
1597 scan the whole files.
1600 @itemx --print-file-name
1601 Print the name of the file before each string.
1604 Print a summary of the program usage on the standard output and exit.
1606 @item -@var{min-len}
1607 @itemx -n @var{min-len}
1608 @itemx --bytes=@var{min-len}
1609 Print sequences of characters that are at least @var{min-len} characters
1610 long, instead of the default 4.
1613 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1614 act like @samp{-t d} instead. Since we can not be compatible with both
1615 ways, we simply chose one.
1617 @item -t @var{radix}
1618 @itemx --radix=@var{radix}
1619 Print the offset within the file before each string. The single
1620 character argument specifies the radix of the offset---@samp{o} for
1621 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1623 @item --target=@var{bfdname}
1624 @cindex object code format
1625 Specify an object code format other than your system's default format.
1626 @xref{Target Selection}, for more information.
1630 Print the program version number on the standard output and exit.
1637 @cindex removing symbols
1638 @cindex discarding symbols
1639 @cindex symbols, discarding
1642 strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1643 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1644 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1645 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1646 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1647 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1648 [ -x | --discard-all ] [ -X | --discard-locals ]
1649 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1650 [ -o @var{file} ] [ -p | --preserve-dates ]
1651 [ -v | --verbose ] [ -V | --version ] [ --help ]
1652 @var{objfile}@dots{}
1655 @sc{gnu} @code{strip} discards all symbols from object files
1656 @var{objfile}. The list of object files may include archives.
1657 At least one object file must be given.
1659 @code{strip} modifies the files named in its argument,
1660 rather than writing modified copies under different names.
1663 @item -F @var{bfdname}
1664 @itemx --target=@var{bfdname}
1665 Treat the original @var{objfile} as a file with the object
1666 code format @var{bfdname}, and rewrite it in the same format.
1667 @xref{Target Selection}, for more information.
1670 Show a summary of the options to @code{strip} and exit.
1672 @item -I @var{bfdname}
1673 @itemx --input-target=@var{bfdname}
1674 Treat the original @var{objfile} as a file with the object
1675 code format @var{bfdname}.
1676 @xref{Target Selection}, for more information.
1678 @item -O @var{bfdname}
1679 @itemx --output-target=@var{bfdname}
1680 Replace @var{objfile} with a file in the output format @var{bfdname}.
1681 @xref{Target Selection}, for more information.
1683 @item -R @var{sectionname}
1684 @itemx --remove-section=@var{sectionname}
1685 Remove any section named @var{sectionname} from the output file. This
1686 option may be given more than once. Note that using this option
1687 inappropriately may make the output file unusable.
1695 @itemx --strip-debug
1696 Remove debugging symbols only.
1698 @item --strip-unneeded
1699 Remove all symbols that are not needed for relocation processing.
1701 @item -K @var{symbolname}
1702 @itemx --keep-symbol=@var{symbolname}
1703 Keep only symbol @var{symbolname} from the source file. This option may
1704 be given more than once.
1706 @item -N @var{symbolname}
1707 @itemx --strip-symbol=@var{symbolname}
1708 Remove symbol @var{symbolname} from the source file. This option may be
1709 given more than once, and may be combined with strip options other than
1713 Put the stripped output in @var{file}, rather than replacing the
1714 existing file. When this argument is used, only one @var{objfile}
1715 argument may be specified.
1718 @itemx --preserve-dates
1719 Preserve the access and modification dates of the file.
1722 @itemx --discard-all
1723 Remove non-global symbols.
1726 @itemx --discard-locals
1727 Remove compiler-generated local symbols.
1728 (These usually start with @samp{L} or @samp{.}.)
1732 Show the version number for @code{strip}.
1736 Verbose output: list all object files modified. In the case of
1737 archives, @samp{strip -v} lists all members of the archive.
1740 @node c++filt, addr2line, strip, Top
1744 @cindex demangling C++ symbols
1747 c++filt [ -_ | --strip-underscores ]
1749 [ -n | --no-strip-underscores ]
1750 [ -s @var{format} | --format=@var{format} ]
1751 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1755 The C++ and Java languages provides function overloading, which means
1756 that you can write many functions with the same name (providing each
1757 takes parameters of different types). All C++ and Java function names
1758 are encoded into a low-level assembly label (this process is known as
1759 @dfn{mangling}). The @code{c++filt}
1760 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1761 MS-DOS this program is named @code{cxxfilt}.}
1762 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1763 names into user-level names so that the linker can keep these overloaded
1764 functions from clashing.
1766 Every alphanumeric word (consisting of letters, digits, underscores,
1767 dollars, or periods) seen in the input is a potential label. If the
1768 label decodes into a C++ name, the C++ name replaces the low-level
1771 You can use @code{c++filt} to decipher individual symbols:
1774 c++filt @var{symbol}
1777 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1778 names from the standard input and writes the demangled names to the
1779 standard output. All results are printed on the standard output.
1783 @itemx --strip-underscores
1784 On some systems, both the C and C++ compilers put an underscore in front
1785 of every name. For example, the C name @code{foo} gets the low-level
1786 name @code{_foo}. This option removes the initial underscore. Whether
1787 @code{c++filt} removes the underscore by default is target dependent.
1791 Prints demangled names using Java syntax. The default is to use C++
1795 @itemx --no-strip-underscores
1796 Do not remove the initial underscore.
1798 @item -s @var{format}
1799 @itemx --format=@var{format}
1800 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1801 different C++ compilers. The argument to this option selects which
1806 the one used by the @sc{gnu} compiler (the default method)
1808 the one used by the Lucid compiler
1810 the one specified by the C++ Annotated Reference Manual
1812 the one used by the HP compiler
1814 the one used by the EDG compiler
1818 Print a summary of the options to @code{c++filt} and exit.
1821 Print the version number of @code{c++filt} and exit.
1825 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1826 user interface are subject to change in future releases. In particular,
1827 a command-line option may be required in the the future to decode a name
1828 passed as an argument on the command line; in other words,
1831 c++filt @var{symbol}
1835 may in a future release become
1838 c++filt @var{option} @var{symbol}
1846 @cindex address to file name and line number
1849 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1851 [ -e @var{filename} | --exe=@var{filename} ]
1852 [ -f | --functions ] [ -s | --basename ]
1853 [ -H | --help ] [ -V | --version ]
1857 @code{addr2line} translates program addresses into file names and line
1858 numbers. Given an address and an executable, it uses the debugging
1859 information in the executable to figure out which file name and line
1860 number are associated with a given address.
1862 The executable to use is specified with the @code{-e} option. The
1863 default is the file @file{a.out}.
1865 @code{addr2line} has two modes of operation.
1867 In the first, hexadecimal addresses are specified on the command line,
1868 and @code{addr2line} displays the file name and line number for each
1871 In the second, @code{addr2line} reads hexadecimal addresses from
1872 standard input, and prints the file name and line number for each
1873 address on standard output. In this mode, @code{addr2line} may be used
1874 in a pipe to convert dynamically chosen addresses.
1876 The format of the output is @samp{FILENAME:LINENO}. The file name and
1877 line number for each address is printed on a separate line. If the
1878 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1879 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1880 containing the address.
1882 If the file name or function name can not be determined,
1883 @code{addr2line} will print two question marks in their place. If the
1884 line number can not be determined, @code{addr2line} will print 0.
1886 The long and short forms of options, shown here as alternatives, are
1890 @item -b @var{bfdname}
1891 @itemx --target=@var{bfdname}
1892 @cindex object code format
1893 Specify that the object-code format for the object files is
1898 @cindex demangling in objdump
1899 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1900 Besides removing any initial underscore prepended by the system, this
1901 makes C++ function names readable. @xref{c++filt}, for more information
1904 @item -e @var{filename}
1905 @itemx --exe=@var{filename}
1906 Specify the name of the executable for which addresses should be
1907 translated. The default file is @file{a.out}.
1911 Display function names as well as file and line number information.
1915 Display only the base of each file name.
1921 @code{nlmconv} converts a relocatable object file into a NetWare
1925 @code{nlmconv} currently works with @samp{i386} object
1926 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1927 object files in @sc{elf}, or @code{a.out} format@footnote{
1928 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1929 format in the Binary File Descriptor library. It has only been tested
1930 with the above formats.}.
1934 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1935 utilities, since it is only useful for NLM targets.
1939 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1940 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1941 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1942 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1943 [ -h | --help ] [ -V | --version ]
1944 @var{infile} @var{outfile}
1947 @code{nlmconv} converts the relocatable @samp{i386} object file
1948 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1949 reading @var{headerfile} for NLM header information. For instructions
1950 on writing the NLM command file language used in header files, see the
1951 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1952 Development and Tools Overview}, which is part of the NLM Software
1953 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1954 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1955 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1958 @code{nlmconv} can perform a link step. In other words, you can list
1959 more than one object file for input if you list them in the definitions
1960 file (rather than simply specifying one input file on the command line).
1961 In this case, @code{nlmconv} calls the linker for you.
1964 @item -I @var{bfdname}
1965 @itemx --input-target=@var{bfdname}
1966 Object format of the input file. @code{nlmconv} can usually determine
1967 the format of a given file (so no default is necessary).
1968 @xref{Target Selection}, for more information.
1970 @item -O @var{bfdname}
1971 @itemx --output-target=@var{bfdname}
1972 Object format of the output file. @code{nlmconv} infers the output
1973 format based on the input format, e.g. for a @samp{i386} input file the
1974 output format is @samp{nlm32-i386}.
1975 @xref{Target Selection}, for more information.
1977 @item -T @var{headerfile}
1978 @itemx --header-file=@var{headerfile}
1979 Reads @var{headerfile} for NLM header information. For instructions on
1980 writing the NLM command file language used in header files, see@ see the
1981 @samp{linkers} section, of the @cite{NLM Development and Tools
1982 Overview}, which is part of the NLM Software Developer's Kit, available
1987 Displays (on standard error) the linker command line used by @code{nlmconv}.
1989 @item -l @var{linker}
1990 @itemx --linker=@var{linker}
1991 Use @var{linker} for any linking. @var{linker} can be an absolute or a
1996 Prints a usage summary.
2000 Prints the version number for @code{nlmconv}.
2006 @code{windres} may be used to manipulate Windows resources.
2009 @emph{Warning:} @code{windres} is not always built as part of the binary
2010 utilities, since it is only useful for Windows targets.
2014 windres [options] [input-file] [output-file]
2017 @code{windres} reads resources from an input file and copies them into
2018 an output file. Either file may be in one of three formats:
2022 A text format read by the Resource Compiler.
2025 A binary format generated by the Resource Compiler.
2028 A COFF object or executable.
2031 The exact description of these different formats is available in
2032 documentation from Microsoft.
2034 When @code{windres} converts from the @code{rc} format to the @code{res}
2035 format, it is acting like the Windows Resource Compiler. When
2036 @code{windres} converts from the @code{res} format to the @code{coff}
2037 format, it is acting like the Windows @code{CVTRES} program.
2039 When @code{windres} generates an @code{rc} file, the output is similar
2040 but not identical to the format expected for the input. When an input
2041 @code{rc} file refers to an external filename, an output @code{rc} file
2042 will instead include the file contents.
2044 If the input or output format is not specified, @code{windres} will
2045 guess based on the file name, or, for the input file, the file contents.
2046 A file with an extension of @file{.rc} will be treated as an @code{rc}
2047 file, a file with an extension of @file{.res} will be treated as a
2048 @code{res} file, and a file with an extension of @file{.o} or
2049 @file{.exe} will be treated as a @code{coff} file.
2051 If no output file is specified, @code{windres} will print the resources
2052 in @code{rc} format to standard output.
2054 The normal use is for you to write an @code{rc} file, use @code{windres}
2055 to convert it to a COFF object file, and then link the COFF file into
2056 your application. This will make the resources described in the
2057 @code{rc} file available to Windows.
2060 @item -i @var{filename}
2061 @itemx --input @var{filename}
2062 The name of the input file. If this option is not used, then
2063 @code{windres} will use the first non-option argument as the input file
2064 name. If there are no non-option arguments, then @code{windres} will
2065 read from standard input. @code{windres} can not read a COFF file from
2068 @item -o @var{filename}
2069 @itemx --output @var{filename}
2070 The name of the output file. If this option is not used, then
2071 @code{windres} will use the first non-option argument, after any used
2072 for the input file name, as the output file name. If there is no
2073 non-option argument, then @code{windres} will write to standard output.
2074 @code{windres} can not write a COFF file to standard output.
2076 @item -I @var{format}
2077 @itemx --input-format @var{format}
2078 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2079 @samp{coff}. If no input format is specified, @code{windres} will
2080 guess, as described above.
2082 @item -O @var{format}
2083 @itemx --output-format @var{format}
2084 The output format to generate. @var{format} may be @samp{res},
2085 @samp{rc}, or @samp{coff}. If no output format is specified,
2086 @code{windres} will guess, as described above.
2088 @item -F @var{target}
2089 @itemx --target @var{target}
2090 Specify the BFD format to use for a COFF file as input or output. This
2091 is a BFD target name; you can use the @code{--help} option to see a list
2092 of supported targets. Normally @code{windres} will use the default
2093 format, which is the first one listed by the @code{--help} option.
2094 @ref{Target Selection}.
2096 @item --preprocessor @var{program}
2097 When @code{windres} reads an @code{rc} file, it runs it through the C
2098 preprocessor first. This option may be used to specify the preprocessor
2099 to use, including any leading arguments. The default preprocessor
2100 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2102 @item --include-dir @var{directory}
2103 Specify an include directory to use when reading an @code{rc} file.
2104 @code{windres} will pass this to the preprocessor as an @code{-I}
2105 option. @code{windres} will also search this directory when looking for
2106 files named in the @code{rc} file.
2108 @item -D @var{target}
2109 @itemx --define @var{sym}[=@var{val}]
2110 Specify a @code{-D} option to pass to the preprocessor when reading an
2114 Enable verbose mode. This tells you what the preprocessor is if you
2117 @item --language @var{val}
2118 Specify the default language to use when reading an @code{rc} file.
2119 @var{val} should be a hexadecimal language code. The low eight bits are
2120 the language, and the high eight bits are the sublanguage.
2123 Prints a usage summary.
2126 Prints the version number for @code{windres}.
2129 If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2130 this will turn on parser debugging.
2135 @chapter Create files needed to build and use DLLs
2139 @code{dlltool} may be used to create the files needed to build and use
2140 dynamic link libraries (DLLs).
2143 @emph{Warning:} @code{dlltool} is not always built as part of the binary
2144 utilities, since it is only useful for those targets which support DLLs.
2148 dlltool [-d|--input-def @var{def-file-name}]
2149 [-b|--base-file @var{base-file-name}]
2150 [-e|--output-exp @var{exports-file-name}]
2151 [-z|--output-def @var{def-file-name}]
2152 [-l|--output-lib @var{library-file-name}]
2153 [--export-all-symbols] [--no-export-all-symbols]
2154 [--exclude-symbols @var{list}]
2155 [--no-default-excludes]
2156 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2157 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2158 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2159 [-A|--add-stdcall-alias]
2160 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2161 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2162 [object-file @dots{}]
2165 @code{dlltool} reads its inputs, which can come from the @samp{-d} and
2166 @samp{-b} options as well as object files specified on the command
2167 line. It then processes these inputs and if the @samp{-e} option has
2168 been specified it creates a exports file. If the @samp{-l} option
2169 has been specified it creates a library file and if the @samp{-z} option
2170 has been specified it creates a def file. Any or all of the -e, -l
2171 and -z options can be present in one invocation of dlltool.
2173 When creating a DLL, along with the source for the DLL, it is necessary
2174 to have three other files. @code{dlltool} can help with the creation of
2177 The first file is a @samp{.def} file which specifies which functions are
2178 exported from the DLL, which functions the DLL imports, and so on. This
2179 is a text file and can be created by hand, or @code{dlltool} can be used
2180 to create it using the @samp{-z} option. In this case @code{dlltool}
2181 will scan the object files specified on its command line looking for
2182 those functions which have been specially marked as being exported and
2183 put entries for them in the .def file it creates.
2185 In order to mark a function as being exported from a DLL, it needs to
2186 have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2187 section of the object file. This can be done in C by using the
2191 asm (".section .drectve");
2192 asm (".ascii \"-export:my_func\"");
2194 int my_func (void) @{ @dots{} @}
2197 The second file needed for DLL creation is an exports file. This file
2198 is linked with the object files that make up the body of the DLL and it
2199 handles the interface between the DLL and the outside world. This is a
2200 binary file and it can be created by giving the @samp{-e} option to
2201 @code{dlltool} when it is creating or reading in a .def file.
2203 The third file needed for DLL creation is the library file that programs
2204 will link with in order to access the functions in the DLL. This file
2205 can be created by giving the @samp{-l} option to dlltool when it
2206 is creating or reading in a .def file.
2208 @code{dlltool} builds the library file by hand, but it builds the
2209 exports file by creating temporary files containing assembler statements
2210 and then assembling these. The @samp{-S} command line option can be
2211 used to specify the path to the assembler that dlltool will use,
2212 and the @samp{-f} option can be used to pass specific flags to that
2213 assembler. The @samp{-n} can be used to prevent dlltool from deleting
2214 these temporary assembler files when it is done, and if @samp{-n} is
2215 specified twice then this will prevent dlltool from deleting the
2216 temporary object files it used to build the library.
2218 Here is an example of creating a DLL from a source file @samp{dll.c} and
2219 also creating a program (from an object file called @samp{program.o})
2224 dlltool -e exports.o -l dll.lib dll.o
2225 gcc dll.o exports.o -o dll.dll
2226 gcc program.o dll.lib -o program
2229 The command line options have the following meanings:
2233 @item -d @var{filename}
2234 @itemx --input-def @var{filename}
2235 @cindex input .def file
2236 Specifies the name of a .def file to be read in and processed.
2238 @item -b @var{filename}
2239 @itemx --base-file @var{filename}
2241 Specifies the name of a base file to be read in and processed. The
2242 contents of this file will be added to the relocation section in the
2243 exports file generated by dlltool.
2245 @item -e @var{filename}
2246 @itemx --output-exp @var{filename}
2247 Specifies the name of the export file to be created by dlltool.
2249 @item -z @var{filename}
2250 @itemx --output-def @var{filename}
2251 Specifies the name of the .def file to be created by dlltool.
2253 @item -l @var{filename}
2254 @itemx --output-lib @var{filename}
2255 Specifies the name of the library file to be created by dlltool.
2257 @item --export-all-symbols
2258 Treat all global and weak defined symbols found in the input object
2259 files as symbols to be exported. There is a small list of symbols which
2260 are not exported by default; see the @code{--no-default-excludes}
2261 option. You may add to the list of symbols to not export by using the
2262 @code{--exclude-symbols} option.
2264 @item --no-export-all-symbols
2265 Only export symbols explicitly listed in an input .def file or in
2266 @samp{.drectve} sections in the input object files. This is the default
2267 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2268 attributes in the source code.
2270 @item --exclude-symbols @var{list}
2271 Do not export the symbols in @var{list}. This is a list of symbol names
2272 separated by comma or colon characters. The symbol names should not
2273 contain a leading underscore. This is only meaningful when
2274 @code{--export-all-symbols} is used.
2276 @item --no-default-excludes
2277 When @code{--export-all-symbols} is used, it will by default avoid
2278 exporting certain special symbols. The current list of symbols to avoid
2279 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2280 @samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2281 to go ahead and export these special symbols. This is only meaningful
2282 when @code{--export-all-symbols} is used.
2285 @itemx --as @var{path}
2286 Specifies the path, including the filename, of the assembler to be used
2287 to create the exports file.
2289 @item -f @var{switches}
2290 @itemx --as-flags @var{switches}
2291 Specifies any specific command line switches to be passed to the
2292 assembler when building the exports file. This option will work even if
2293 the @samp{-S} option is not used. This option only takes one argument,
2294 and if it occurs more than once on the command line, then later
2295 occurrences will override earlier occurrences. So if it is necessary to
2296 pass multiple switches to the assembler they should be enclosed in
2300 @itemx --dll-name @var{name}
2301 Specifies the name to be stored in the .def file as the name of the DLL
2302 when the @samp{-e} option is used. If this option is not present, then
2303 the filename given to the @samp{-e} option will be used as the name of
2306 @item -m @var{machine}
2307 @itemx -machine @var{machine}
2308 Specifies the type of machine for which the library file should be
2309 built. @code{dlltool} has a built in default type, depending upon how
2310 it was created, but this option can be used to override that. This is
2311 normally only useful when creating DLLs for an ARM processor, when the
2312 contents of the DLL are actually encode using THUMB instructions.
2315 @itemx --add-indirect
2316 Specifies that when @code{dlltool} is creating the exports file it
2317 should add a section which allows the exported functions to be
2318 referenced without using the import library. Whatever the hell that
2322 @itemx --add-underscore
2323 Specifies that when @code{dlltool} is creating the exports file it
2324 should prepend an underscore to the names of the exported functions.
2328 Specifies that when @code{dlltool} is creating the exports file it
2329 should not append the string @samp{@@ <number>}. These numbers are
2330 called ordinal numbers and they represent another way of accessing the
2331 function in a DLL, other than by name.
2334 @itemx --add-stdcall-alias
2335 Specifies that when @code{dlltool} is creating the exports file it
2336 should add aliases for stdcall symbols without @samp{@@ <number>}
2337 in addition to the symbols with @samp{@@ <number>}.
2341 Specifies that when @code{dlltool} is creating the exports and library
2342 files it should omit the .idata4 section. This is for compatibility
2343 with certain operating systems.
2347 Specifies that when @code{dlltool} is creating the exports and library
2348 files it should omit the .idata5 section. This is for compatibility
2349 with certain operating systems.
2353 Specifies that @code{dlltool} should mark the objects in the library
2354 file and exports file that it produces as supporting interworking
2355 between ARM and THUMB code.
2359 Makes @code{dlltool} preserve the temporary assembler files it used to
2360 create the exports file. If this option is repeated then dlltool will
2361 also preserve the temporary object files it uses to create the library
2366 Make dlltool describe what it is doing.
2370 Displays a list of command line options and then exits.
2374 Displays dlltool's version number and then exits.
2381 @cindex ELF file information
2385 readelf [ -a | --all ]
2386 [ -h | --file-header]
2387 [ -l | --program-headers | --segments]
2388 [ -S | --section-headers | --sections]
2390 [ -s | --syms | --symbols]
2394 [ -V | --version-info]
2395 [ -D | --use-dynamic]
2396 [ -x <number> | --hex-dump=<number>]
2397 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2401 @var{elffile}@dots{}
2404 @code{readelf} displays information about one or more ELF format object
2405 files. The options control what particular information to display.
2407 @var{elffile}@dots{} are the object files to be examined. At the
2408 moment, @code{readelf} does not support examining archives, nor does it
2409 support examing 64 bit ELF files.
2411 The long and short forms of options, shown here as alternatives, are
2412 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2418 Equivalent to specifiying @samp{--file-header},
2419 @samp{--program-headers}, @samp{--sections}, @samp{--symbols},
2420 @samp{--relocs}, @samp{--dynamic}, @samp{--notes} and
2421 @samp{--version-info}.
2424 @itemx --file-header
2425 @cindex ELF file header information
2426 Displays the information contained in the ELF header at the start of the
2430 @itemx --program-headers
2432 @cindex ELF program header information
2433 @cindex ELF segment information
2434 Displays the information contained in the file's segment headers, if it
2439 @itemx --section-headers
2440 @cindex ELF section information
2441 Displays the information contained in the file's section headers, if it
2447 @cindex ELF symbol table information
2448 Displays the entries in symbol table section of the file, if it has one.
2452 Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2456 @cindex ELF core notes
2457 Displays the contents of the NOTE segment, if it exists.
2461 @cindex ELF reloc information
2462 Displays the contents of the file's relocation section, if it ha one.
2466 @cindex ELF dynamic section information
2467 Displays the contents of the file's dynamic section, if it has one.
2470 @itemx --version-info
2471 @cindex ELF version sections informations
2472 Displays the contents of the version sections in the file, it they
2476 @itemx --use-dynamic
2477 When displaying symbols, this option makes @code{readelf} use the
2478 symblol table in the file's dynamic section, rather than the one in the
2482 @itemx --hex-dump=<number>
2483 Displays the contents of the indicated section as a hexadecimal dump.
2486 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2487 Displays the contents of the debug sections in the file, if any are
2488 present. If one of the optional letters or words follows the switch
2489 then only data found in those specific sections will be dumped.
2492 Display a histogram of bucket list lengths when displaying the contents
2493 of the symbol tables.
2497 Display the version number of readelf.
2501 Display the command line options understood by @code{readelf}.
2506 @node Selecting The Target System
2507 @chapter Selecting the target system
2509 You can specify three aspects of the target system to the @sc{gnu}
2510 binary file utilities, each in several ways:
2520 the linker emulation (which applies to the linker only)
2523 In the following summaries, the lists of ways to specify values are in
2524 order of decreasing precedence. The ways listed first override those
2527 The commands to list valid values only list the values for which the
2528 programs you are running were configured. If they were configured with
2529 @samp{--enable-targets=all}, the commands list most of the available
2530 values, but a few are left out; not all targets can be configured in at
2531 once because some of them can only be configured @dfn{native} (on hosts
2532 with the same type as the target system).
2535 * Target Selection::
2536 * Architecture Selection::
2537 * Linker Emulation Selection::
2540 @node Target Selection
2541 @section Target Selection
2543 A @dfn{target} is an object file format. A given target may be
2544 supported for multiple architectures (@pxref{Architecture Selection}).
2545 A target selection may also have variations for different operating
2546 systems or architectures.
2548 The command to list valid target values is @samp{objdump -i}
2549 (the first column of output contains the relevant information).
2551 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2552 @samp{a.out-sunos-big}.
2554 You can also specify a target using a configuration triplet. This is
2555 the same sort of name that is passed to @file{configure} to specify a
2556 target. When you use a configuration triplet as an argument, it must be
2557 fully canonicalized. You can see the canonical version of a triplet by
2558 running the shell script @file{config.sub} which is included with the
2561 Some sample configuration triplets are: @samp{m68k-hp-bsd},
2562 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2564 @subheading @code{objdump} Target
2570 command line option: @samp{-b} or @samp{--target}
2573 environment variable @code{GNUTARGET}
2576 deduced from the input file
2579 @subheading @code{objcopy} and @code{strip} Input Target
2585 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2588 environment variable @code{GNUTARGET}
2591 deduced from the input file
2594 @subheading @code{objcopy} and @code{strip} Output Target
2600 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2603 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2606 environment variable @code{GNUTARGET}
2609 deduced from the input file
2612 @subheading @code{nm}, @code{size}, and @code{strings} Target
2618 command line option: @samp{--target}
2621 environment variable @code{GNUTARGET}
2624 deduced from the input file
2627 @subheading Linker Input Target
2633 command line option: @samp{-b} or @samp{--format}
2634 (@pxref{Options,,Options,ld.info,Using LD})
2637 script command @code{TARGET}
2638 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2641 environment variable @code{GNUTARGET}
2642 (@pxref{Environment,,Environment,ld.info,Using LD})
2645 the default target of the selected linker emulation
2646 (@pxref{Linker Emulation Selection})
2649 @subheading Linker Output Target
2655 command line option: @samp{-oformat}
2656 (@pxref{Options,,Options,ld.info,Using LD})
2659 script command @code{OUTPUT_FORMAT}
2660 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2663 the linker input target (see ``Linker Input Target'' above)
2666 @node Architecture Selection
2667 @section Architecture selection
2669 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2670 to run. Its name may contain a colon, separating the name of the
2671 processor family from the name of the particular @sc{cpu}.
2673 The command to list valid architecture values is @samp{objdump -i} (the
2674 second column contains the relevant information).
2676 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2678 @subheading @code{objdump} Architecture
2684 command line option: @samp{-m} or @samp{--architecture}
2687 deduced from the input file
2690 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2696 deduced from the input file
2699 @subheading Linker Input Architecture
2705 deduced from the input file
2708 @subheading Linker Output Architecture
2714 script command @code{OUTPUT_ARCH}
2715 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2718 the default architecture from the linker output target
2719 (@pxref{Target Selection})
2722 @node Linker Emulation Selection
2723 @section Linker emulation selection
2725 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2726 the linker default values for the other aspects of the target system.
2727 In particular, it consists of
2737 several ``hook'' functions that are run at certain stages of the linking
2738 process to do special things that some targets require
2741 The command to list valid linker emulation values is @samp{ld -V}.
2743 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2749 command line option: @samp{-m}
2750 (@pxref{Options,,Options,ld.info,Using LD})
2753 environment variable @code{LDEMULATION}
2756 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2757 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2760 @node Reporting Bugs
2761 @chapter Reporting Bugs
2763 @cindex reporting bugs
2765 Your bug reports play an essential role in making the binary utilities
2768 Reporting a bug may help you by bringing a solution to your problem, or
2769 it may not. But in any case the principal function of a bug report is
2770 to help the entire community by making the next version of the binary
2771 utilities work better. Bug reports are your contribution to their
2774 In order for a bug report to serve its purpose, you must include the
2775 information that enables us to fix the bug.
2778 * Bug Criteria:: Have you found a bug?
2779 * Bug Reporting:: How to report bugs
2783 @section Have you found a bug?
2784 @cindex bug criteria
2786 If you are not sure whether you have found a bug, here are some guidelines:
2789 @cindex fatal signal
2792 If a binary utility gets a fatal signal, for any input whatever, that is
2793 a bug. Reliable utilities never crash.
2795 @cindex error on valid input
2797 If a binary utility produces an error message for valid input, that is a
2801 If you are an experienced user of binary utilities, your suggestions for
2802 improvement are welcome in any case.
2806 @section How to report bugs
2808 @cindex bugs, reporting
2810 A number of companies and individuals offer support for @sc{gnu}
2811 products. If you obtained the binary utilities from a support
2812 organization, we recommend you contact that organization first.
2814 You can find contact information for many support companies and
2815 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2818 In any event, we also recommend that you send bug reports for the binary
2819 utilities to @samp{bug-gnu-utils@@gnu.org}.
2821 The fundamental principle of reporting bugs usefully is this:
2822 @strong{report all the facts}. If you are not sure whether to state a
2823 fact or leave it out, state it!
2825 Often people omit facts because they think they know what causes the
2826 problem and assume that some details do not matter. Thus, you might
2827 assume that the name of a file you use in an example does not matter.
2828 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2829 a stray memory reference which happens to fetch from the location where
2830 that pathname is stored in memory; perhaps, if the pathname were
2831 different, the contents of that location would fool the utility into
2832 doing the right thing despite the bug. Play it safe and give a
2833 specific, complete example. That is the easiest thing for you to do,
2834 and the most helpful.
2836 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2837 it is new to us. Therefore, always write your bug reports on the assumption
2838 that the bug has not been reported previously.
2840 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2841 bell?'' Those bug reports are useless, and we urge everyone to
2842 @emph{refuse to respond to them} except to chide the sender to report
2845 To enable us to fix the bug, you should include all these things:
2849 The version of the utility. Each utility announces it if you start it
2850 with the @samp{--version} argument.
2852 Without this, we will not know whether there is any point in looking for
2853 the bug in the current version of the binary utilities.
2856 Any patches you may have applied to the source, including any patches
2857 made to the @code{BFD} library.
2860 The type of machine you are using, and the operating system name and
2864 What compiler (and its version) was used to compile the utilities---e.g.
2868 The command arguments you gave the utility to observe the bug. To
2869 guarantee you will not omit something important, list them all. A copy
2870 of the Makefile (or the output from make) is sufficient.
2872 If we were to try to guess the arguments, we would probably guess wrong
2873 and then we might not encounter the bug.
2876 A complete input file, or set of input files, that will reproduce the
2877 bug. If the utility is reading an object file or files, then it is
2878 generally most helpful to send the actual object files, uuencoded if
2879 necessary to get them through the mail system. Note that
2880 @samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2881 sending very large files to it. Making the files available for
2882 anonymous FTP is OK.
2884 If the source files were produced exclusively using @sc{gnu} programs
2885 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2886 may be OK to send the source files rather than the object files. In
2887 this case, be sure to say exactly what version of @code{gcc}, or
2888 whatever, was used to produce the object files. Also say how
2889 @code{gcc}, or whatever, was configured.
2892 A description of what behavior you observe that you believe is
2893 incorrect. For example, ``It gets a fatal signal.''
2895 Of course, if the bug is that the utility gets a fatal signal, then we
2896 will certainly notice it. But if the bug is incorrect output, we might
2897 not notice unless it is glaringly wrong. You might as well not give us
2898 a chance to make a mistake.
2900 Even if the problem you experience is a fatal signal, you should still
2901 say so explicitly. Suppose something strange is going on, such as your
2902 copy of the utility is out of synch, or you have encountered a bug in
2903 the C library on your system. (This has happened!) Your copy might
2904 crash and ours would not. If you told us to expect a crash, then when
2905 ours fails to crash, we would know that the bug was not happening for
2906 us. If you had not told us to expect a crash, then we would not be able
2907 to draw any conclusion from our observations.
2910 If you wish to suggest changes to the source, send us context diffs, as
2911 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2912 option. Always send diffs from the old file to the new file. If you
2913 wish to discuss something in the @code{ld} source, refer to it by
2914 context, not by line number.
2916 The line numbers in our development sources will not match those in your
2917 sources. Your line numbers would convey no useful information to us.
2920 Here are some things that are not necessary:
2924 A description of the envelope of the bug.
2926 Often people who encounter a bug spend a lot of time investigating
2927 which changes to the input file will make the bug go away and which
2928 changes will not affect it.
2930 This is often time consuming and not very useful, because the way we
2931 will find the bug is by running a single example under the debugger
2932 with breakpoints, not by pure deduction from a series of examples.
2933 We recommend that you save your time for something else.
2935 Of course, if you can find a simpler example to report @emph{instead}
2936 of the original one, that is a convenience for us. Errors in the
2937 output will be easier to spot, running under the debugger will take
2938 less time, and so on.
2940 However, simplification is not vital; if you do not want to do this,
2941 report the bug anyway and send us the entire test case you used.
2944 A patch for the bug.
2946 A patch for the bug does help us if it is a good one. But do not omit
2947 the necessary information, such as the test case, on the assumption that
2948 a patch is all we need. We might see problems with your patch and decide
2949 to fix the problem another way, or we might not understand it at all.
2951 Sometimes with programs as complicated as the binary utilities it is
2952 very hard to construct an example that will make the program follow a
2953 certain path through the code. If you do not send us the example, we
2954 will not be able to construct one, so we will not be able to verify that
2957 And if we cannot understand what bug you are trying to fix, or why your
2958 patch should be an improvement, we will not install it. A test case will
2959 help us to understand.
2962 A guess about what the bug is or what it depends on.
2964 Such guesses are usually wrong. Even we cannot guess right about such
2965 things without first using the debugger to find the facts.