NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT | COLOPHON

AR(1)                       GNU Development Tools                      AR(1)

NAME         top

       ar - create, modify, and extract from archives

SYNOPSIS         top

       ar [-X32_64] [-]p[mod] [--plugin name] [--target bfdname] [relpos]
       [count] archive [member...]

DESCRIPTION         top

       The GNU ar program creates, modifies, and extracts from archives.  An
       archive is a single file holding a collection of other files in a
       structure that makes it possible to retrieve the original individual
       files (called members of the archive).
       The original files' contents, mode (permissions), timestamp, owner,
       and group are preserved in the archive, and can be restored on
       extraction.
       GNU ar can maintain archives whose members have names of any length;
       however, depending on how ar is configured on your system, a limit on
       member-name length may be imposed for compatibility with archive
       formats maintained with other tools.  If it exists, the limit is
       often 15 characters (typical of formats related to a.out) or 16
       characters (typical of formats related to coff).
       ar is considered a binary utility because archives of this sort are
       most often used as libraries holding commonly needed subroutines.
       ar creates an index to the symbols defined in relocatable object
       modules in the archive when you specify the modifier s.  Once
       created, this index is updated in the archive whenever ar makes a
       change to its contents (save for the q update operation).  An archive
       with such an index speeds up linking to the library, and allows
       routines in the library to call each other without regard to their
       placement in the archive.
       You may use nm -s or nm --print-armap to list this index table.  If
       an archive lacks the table, another form of ar called ranlib can be
       used to add just the table.
       GNU ar can optionally create a thin archive, which contains a symbol
       index and references to the original copies of the member files of
       the archive.  This is useful for building libraries for use within a
       local build tree, where the relocatable objects are expected to
       remain available, and copying the contents of each object would only
       waste time and space.
       An archive can either be thin or it can be normal.  It cannot be both
       at the same time.  Once an archive is created its format cannot be
       changed without first deleting it and then creating a new archive in
       its place.
       Thin archives are also flattened, so that adding one thin archive to
       another thin archive does not nest it, as would happen with a normal
       archive.  Instead the elements of the first archive are added
       individually to the second archive.
       The paths to the elements of the archive are stored relative to the
       archive itself.
       GNU ar is designed to be compatible with two different facilities.
       You can control its activity using command-line options, like the
       different varieties of ar on Unix systems; or, if you specify the
       single command-line option -M, you can control it with a script
       supplied via standard input, like the MRI "librarian" program.

OPTIONS         top

       GNU ar allows you to mix the operation code p and modifier flags mod
       in any order, within the first command-line argument.
       If you wish, you may begin the first command-line argument with a
       dash.
       The p keyletter specifies what operation to execute; it may be any of
       the following, but you must specify only one of them:
       d   Delete modules from the archive.  Specify the names of modules to
           be deleted as member...; the archive is untouched if you specify
           no files to delete.
           If you specify the v modifier, ar lists each module as it is
           deleted.
       m   Use this operation to move members in an archive.
           The ordering of members in an archive can make a difference in
           how programs are linked using the library, if a symbol is defined
           in more than one member.
           If no modifiers are used with "m", any members you name in the
           member arguments are moved to the end of the archive; you can use
           the a, b, or i modifiers to move them to a specified place
           instead.
       p   Print the specified members of the archive, to the standard
           output file.  If the v modifier is specified, show the member
           name before copying its contents to standard output.
           If you specify no member arguments, all the files in the archive
           are printed.
       q   Quick append; Historically, add the files member... to the end of
           archive, without checking for replacement.
           The modifiers a, b, and i do not affect this operation; new
           members are always placed at the end of the archive.
           The modifier v makes ar list each file as it is appended.
           Since the point of this operation is speed, implementations of ar
           have the option of not updating the archive's symbol table if one
           exists.  Too many different systems however assume that symbol
           tables are always up-to-date, so GNU ar will rebuild the table
           even with a quick append.
           Note - GNU ar treats the command qs as a synonym for r -
           replacing already existing files in the archive and appending new
           ones at the end.
       r   Insert the files member... into archive (with replacement). This
           operation differs from q in that any previously existing members
           are deleted if their names match those being added.
           If one of the files named in member... does not exist, ar
           displays an error message, and leaves undisturbed any existing
           members of the archive matching that name.
           By default, new members are added at the end of the file; but you
           may use one of the modifiers a, b, or i to request placement
           relative to some existing member.
           The modifier v used with this operation elicits a line of output
           for each file inserted, along with one of the letters a or r to
           indicate whether the file was appended (no old member deleted) or
           replaced.
       s   Add an index to the archive, or update it if it already exists.
           Note this command is an exception to the rule that there can only
           be one command letter, as it is possible to use it as either a
           command or a modifier.  In either case it does the same thing.
       t   Display a table listing the contents of archive, or those of the
           files listed in member... that are present in the archive.
           Normally only the member name is shown; if you also want to see
           the modes (permissions), timestamp, owner, group, and size, you
           can request that by also specifying the v modifier.
           If you do not specify a member, all files in the archive are
           listed.
           If there is more than one file with the same name (say, fie) in
           an archive (say b.a), ar t b.a fie lists only the first instance;
           to see them all, you must ask for a complete listing---in our
           example, ar t b.a.
       x   Extract members (named member) from the archive.  You can use the
           v modifier with this operation, to request that ar list each name
           as it extracts it.
           If you do not specify a member, all files in the archive are
           extracted.
           Files cannot be extracted from a thin archive.
       --help
           Displays the list of command line options supported by ar and
           then exits.
       --version
           Displays the version information of ar and then exits.
       A number of modifiers (mod) may immediately follow the p keyletter,
       to specify variations on an operation's behavior:
       a   Add new files after an existing member of the archive.  If you
           use the modifier a, the name of an existing archive member must
           be present as the relpos argument, before the archive
           specification.
       b   Add new files before an existing member of the archive.  If you
           use the modifier b, the name of an existing archive member must
           be present as the relpos argument, before the archive
           specification.  (same as i).
       c   Create the archive.  The specified archive is always created if
           it did not exist, when you request an update.  But a warning is
           issued unless you specify in advance that you expect to create
           it, by using this modifier.
       D   Operate in deterministic mode.  When adding files and the archive
           index use zero for UIDs, GIDs, timestamps, and use consistent
           file modes for all files.  When this option is used, if ar is
           used with identical options and identical input files, multiple
           runs will create identical output files regardless of the input
           files' owners, groups, file modes, or modification times.
           If binutils was configured with --enable-deterministic-archives,
           then this mode is on by default.  It can be disabled with the U
           modifier, below.
       f   Truncate names in the archive.  GNU ar will normally permit file
           names of any length.  This will cause it to create archives which
           are not compatible with the native ar program on some systems.
           If this is a concern, the f modifier may be used to truncate file
           names when putting them in the archive.
       i   Insert new files before an existing member of the archive.  If
           you use the modifier i, the name of an existing archive member
           must be present as the relpos argument, before the archive
           specification.  (same as b).
       l   This modifier is accepted but not used.
       N   Uses the count parameter.  This is used if there are multiple
           entries in the archive with the same name.  Extract or delete
           instance count of the given name from the archive.
       o   Preserve the original dates of members when extracting them.  If
           you do not specify this modifier, files extracted from the
           archive are stamped with the time of extraction.
       P   Use the full path name when matching names in the archive.  GNU
           ar can not create an archive with a full path name (such archives
           are not POSIX complaint), but other archive creators can.  This
           option will cause GNU ar to match file names using a complete
           path name, which can be convenient when extracting a single file
           from an archive created by another tool.
       s   Write an object-file index into the archive, or update an
           existing one, even if no other change is made to the archive.
           You may use this modifier flag either with any operation, or
           alone.  Running ar s on an archive is equivalent to running
           ranlib on it.
       S   Do not generate an archive symbol table.  This can speed up
           building a large library in several steps.  The resulting archive
           can not be used with the linker.  In order to build a symbol
           table, you must omit the S modifier on the last execution of ar,
           or you must run ranlib on the archive.
       T   Make the specified archive a thin archive.  If it already exists
           and is a regular archive, the existing members must be present in
           the same directory as archive.
       u   Normally, ar r... inserts all files listed into the archive.  If
           you would like to insert only those of the files you list that
           are newer than existing members of the same names, use this
           modifier.  The u modifier is allowed only for the operation r
           (replace).  In particular, the combination qu is not allowed,
           since checking the timestamps would lose any speed advantage from
           the operation q.
       U   Do not operate in deterministic mode.  This is the inverse of the
           D modifier, above: added files and the archive index will get
           their actual UID, GID, timestamp, and file mode values.
           This is the default unless binutils was configured with
           --enable-deterministic-archives.
       v   This modifier requests the verbose version of an operation.  Many
           operations display additional information, such as filenames
           processed, when the modifier v is appended.
       V   This modifier shows the version number of ar.
       ar ignores an initial option spelt -X32_64, for compatibility with
       AIX.  The behaviour produced by this option is the default for GNU
       ar.  ar does not support any of the other -X options; in particular,
       it does not support -X32 which is the default for AIX ar.
       The optional command line switch --plugin name causes ar to load the
       plugin called name which adds support for more file formats.  This
       option is only available if the toolchain has been built with plugin
       support enabled.
       The optional command line switch --target bfdname specifies that the
       archive members are in an object code format different from your
       system's default format.  See
       @file
           Read command-line options from file.  The options read are
           inserted in place of the original @file option.  If file does not
           exist, or cannot be read, then the option will be treated
           literally, and not removed.
           Options in file are separated by whitespace.  A whitespace
           character may be included in an option by surrounding the entire
           option in either single or double quotes.  Any character
           (including a backslash) may be included by prefixing the
           character to be included with a backslash.  The file may itself
           contain additional @file options; any such options will be
           processed recursively.

SEE ALSO         top

       nm(1), ranlib(1), and the Info entries for binutils.

COPYRIGHT         top

       Copyright (c) 1991-2017 Free Software Foundation, Inc.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is included in the section entitled
       "GNU Free Documentation License".

COLOPHON         top

       This page is part of the binutils (a collection of tools for working
       with executable binaries) project.  Information about the project can
       be found at ⟨http://www.gnu.org/software/binutils/⟩.  If you have a
       bug report for this manual page, see 
       ⟨http://sourceware.org/bugzilla/enter_bug.cgi?product=binutils⟩.  This
       page was obtained from the tarball binutils-2.28.tar.gz fetched from
       ⟨https://ftp.gnu.org/gnu/binutils/⟩ on 2017-07-05.  If you discover
       any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page, or
       you have corrections or improvements to the information in this
       COLOPHON (which is not part of the original manual page), send a mail
       to man-pages@man7.org
binutils-2.28                    2017-03-02                            AR(1)

Pages that refer to this page: uselib(2)