AR(1)

📦 version 2.47, in arch rolling

👑 AR(1) — or, "bestie, let me introduce you to ar" 💅

okay so this is the GNU Development Tools manual page for ar — yes, the manual page is literally called AR(1) in the header, but we're not doing that stiff energy here. This is your girl explaining ar to you like you're sitting next to me in the library at 2am. Stay with me, it's gonna slay. 🫶

✨ NAME ✨

ar — create, modify, and extract from archives. that's the whole vibe. 🎀

🌸 SYNOPSIS 🌸

like, here's the shape of the thing:

ar [-X32_64]
   [-]p[mod]
   [--plugin name]
   [--target bfdname]
   [--output dirname]
   [--record-libdeps libdeps]
   [--thin]
   [relpos] [count] archive [member...]  ar -M [< mri-script]

iconic. no notes. 🔥

💖 DESCRIPTION 💖

okay so the GNU ar program creates, modifies, and extracts from archives. and what IS an archive, you ask? it's a single file holding a whole collection of other files, arranged in a structure so you can get the original individual files back out later. those individual files are called members of the archive. it's giving "one suitcase, many outfits". 🧳✨

the original files' contents, mode (permissions), timestamp, owner, and group are all preserved in the archive, and can be restored on extraction. nothing gets lost, no cap. 💯

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). so like, don't come crying to me if your 40-char filename gets chopped. 🙈

ar is considered a binary utility because archives of this sort are most often used as libraries holding commonly needed subroutines. and since libraries often will depend on other libraries, ar can also record the dependencies of a library when the --record-libdeps option is specified. teamwork makes the dream work fr fr. 🫶

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, mind you, that's the one exception. an archive with such an index speeds up linking to the library, so it's lowkey a glow-up for your link times. ⚡

you may use nm -s or nm --print-armap to list this index table. and if an archive lacks the table? there's another form of ar called ranlib that can be used to add just the table. she's the specialist. 👑

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. super 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. why duplicate when you can point? 🦋

an archive can either be thin or it can be normal. it cannot be both at the same time — pick a lane bestie. and once an archive is created, its format cannot be changed without first deleting it and then creating a new archive in its place. so, like, think before you commit. 💀

thin archives are also flattened, so that adding one thin archive to another thin archive does not nest it, the way it would happen with a normal archive. instead the elements of the first archive are added individually to the second archive. no nesting dolls here, only flat lay energy. 🎀

the paths to the elements of the archive are stored relative to the archive itself. important detail, don't forget it. 📌

GNU ar is designed to be compatible with two different facilities, which is honestly main character behavior:

  • 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.

two personalities, both slay. 💅

⭐ OPTIONS ⭐

GNU ar lets you mix the operation code p and modifier flags mod in any order, within the first command-line argument. any order!! live your truth. 🌈

and if you wish, you may begin the first command-line argument with a dash. optional dash, we're chill like that. ✨

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. bye bye babes 👋
  • 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. relocation era 🚚
  • 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. show and tell 🖨️
  • 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 — but too many different systems 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. plot twist but make it convenient. 😭
  • 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. protective queen. 🛡️ 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. multitalented icon. 🌟
  • 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, but if the modifier O is specified, then the corresponding offset of the member is also displayed. finally, in order to see the modes (permissions), timestamp, owner, group, and size, the v modifier should be included. 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. 💜
big warning energy — files cannot be extracted from a thin archive, and there are restrictions on extracting from archives created with P: the paths must not be absolute, may not contain .., and any subdirectories in the paths must exist. if it is desired to avoid these restrictions then use the --output option to specify an output directory. don't say I didn't warn you. 😭

🎀 the modifiers (mod) 🎀

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. consent matters, even for filesystems 💅
  • 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. reproducibility slay ✨ if binutils was configured with --enable-deterministic-archives, then this mode is on by default. it can be disabled with the U modifier, below. ({your girl has not gotten to U yet — part 2 energy, iykyk} 😌)
  • 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 — Specify dependencies of this library. the dependencies must immediately follow this option character, must use the same syntax as the linker command line, and must be specified within a single argument. i.e., if multiple items are needed, they must be quoted to form a single command line argument. for example: l "-L/usr/local/lib -lmydep1 -lmydep2". quote it or regret it, bestie 🫶
  • 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. when there's a whole squad of same-named files and you need to call out a specific one 🔢
  • 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. nostalgia mode: on 🕰️
  • O — Display member offsets inside the archive. use together with the t option. 🎯
  • P — Use the full path name when matching or storing names in the archive. archives created with full path names are not POSIX compliant, and thus may not work with tools other than up to date GNU tools. modifying such archives with GNU ar without using P will remove the full path names unless the archive is a thin archive. note that P may be useful when adding files to a thin archive since r without P ignores the path when choosing which element to replace. thus

thus… 🌸 (to be continued in part 2 — we literally stopped mid-sentence, the suspense is unreal)

ar rcST archive.a subdir/file1 subdir/file2 file1

so this is what actually goes down: the first subdir/file1 gets replaced with file1 from your current directory. and if you add P it stops that replacement from happening. that's it, that's the whole drama 💅

  • s — writes an object-file index into the archive, or updates one that's already there, even if literally nothing else about the archive changed. you can use this modifier with any operation, or just on its own as a solo main character moment. running ar s on an archive? same energy as running ranlib on it. no cap ✨
  • S — do not generate an archive symbol table. this can speed up building a big library across several steps, but it will negatively impact performance if you then use the resulting archive with the linker. so to actually build that symbol table you either omit the S modifier on your last run of ar, or you run ranlib on the archive. pick your fighter 🫶
  • T — deprecated alias for --thin. it is not recommended, because in a lot of ar implementations T means something completely different, as specified by X/Open System Interface. it's giving "don't do it, bestie" 💀
  • u — normally ar r... inserts all the files you list into the archive. if you only want to insert the ones that are newer than existing members with the same names, use this modifier. u is only allowed with the operation r (replace). in particular, qu is not allowed — because checking timestamps would destroy the entire speed advantage you get from q. 🙈
heads up — if an archive was created in a deterministic manner, eg via the D modifier, then replacement will always happen and the u modifier will be completely ineffective. like, it just won't do anything. 😭
  • U — do not operate in deterministic mode. this is the inverse of the D modifier above: added files and the archive index get their actual UID, GID, timestamp, and file mode values. this is the default, unless binutils was configured with --enable-deterministic-archives.
  • v — requests the verbose version of an operation. a lot of operations show extra info, like which filenames were processed, when the v modifier is appended. very "tell me everything" of it 🔥
  • V — shows the version number of ar. iconic.

the ar program also supports some command-line options that are neither modifiers nor actions, but which do change how it behaves in specific ways. so like, a whole third category, because of course:

  • --help — displays the list of command-line options supported by ar, then exits. cute and useful 🌸
  • --version — displays the version information of ar, then exits.
  • -X32_64 — ar ignores an initial option spelled -X32_64, for compatibility with AIX. the behaviour this option produces is the default for GNU ar anyway. ar does not support any of the other -X options — in particular it does not support -X32, which is the default for AIX ar. don't come for us with AIX options, we're not doing that today 🧚
  • --plugin _name_ — the optional command-line switch --plugin name causes ar to load the plugin called _name_, which adds support for more file formats, including object files with link-time optimization information. 🦋
    • this option is only available if the toolchain has been built with plugin support enabled.
    • if --plugin is not provided, but plugin support has been enabled, then ar iterates over the files in ${libdir}/bfd-plugins in alphabetic order and the first plugin that claims the object in question is used.
    • please note that this plugin search directory is not the one used by ld's -plugin option. in order to make ar use the linker plugin, it must be copied into the ${libdir}/bfd-plugins directory. for GCC based compilations the linker plugin is called liblto_plugin.so.0.0.0. for Clang based compilations it is called LLVMgold.so. the GCC plugin is always backwards compatible with earlier versions, so it is sufficient to just copy the newest one. 💖
  • --target _target_ — 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
that's literally where the sentence ends in the original. just "See". no link, no nothing. i'm not making that up, i would never do you like that 😭
  • --output _dirname_ — the --output option can be used to specify a path to a directory into which archive members should be extracted. if this option is not specified then the current directory will be used.
note — although the presence of this option does imply a x extraction operation, that option must still be included on the command line. so yes, you have to say it out loud. no mind reading 📣
  • --record-libdeps _libdeps_ — the --record-libdeps option is identical to the l modifier, just handled in long form. twins fr fr 👑
  • --thin — 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_. 🎀
  • @_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 ✨

nm(1), ranlib(1), and the Info entries for binutils. go read them, they're right there, hydrate and educate 💜

Copyright (c) 1991-2026 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".

and that's the whole page, bestie!! this was binutils-2.47, dated 2026-07-30, and it will forever be known as AR(1) in my heart. go archive something iconic 💅✨🦋

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