AR(1)

📦 version 2.47, in arch rolling

💖 NAME 💖

ar — create, modify, and extract from archives. This is ar from GNU Development Tools, aka the archive queen, and she is literally here to make your library era iconic 💅

✨ SYNOPSIS ✨

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

🦋 DESCRIPTION 🦋

Okay so 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 — those are called members of the archive. cute concept, honestly 🎀

The original files' contents, mode (permissions), timestamp, owner, and group are preserved in the archive, and can be restored on extraction. yes bestie, she keeps the whole vibe intact ✨

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 yeah, sometimes there is a name-length situation, lowkey tragic but real 😭

ar is considered a binary utility because archives of this sort are most often used as libraries holding commonly needed subroutines. Since libraries often will depend on other libraries, ar can also record the dependencies of a library when the --record-libdeps option is specified. she's not just organizing files, she's keeping the dependency lore 🫶

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. that's the good stuff right there 🔥

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. she has a whole little sibling for that one job, iconic 💅

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. efficiency slay ✨

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.

⚠️ bestie, that format-lock is serious: no little in-place glow-up from thin to normal or normal to thin. delete and recreate, or leave it alone.

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. no nesting drama, just flat and cute 🦋

The paths to the elements of the archive are stored relative to the archive itself. noted, bestie 🌸

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. two modes, both valid, main character energy 👑

🎀 OPTIONS 🎀

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. bye-bye, members 💀
  • 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. rearrange her little archive shelves 🧚
  • 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. spill the archive contents, literally 💅
  • 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. fast append, but GNU ar still keeps the table current, no cap 🔥
  • 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. replacement era, but with receipts 🫶
  • 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. she's flexible like that, and still on brand ✨
  • 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. peek at the archive menu, bestie 👀
  • 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, 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. extraction time, but read the thin-archive and P-archive fine print first 😭

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. after this member, periodt 💅
  • 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). before this member, cute and clear 🎀
  • 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. she's like “bestie, say you meant to make a new archive” ⭐
  • 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. deterministic queen, reproducible output, obsessed 🌈
  • 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. short names for compatibility, but only if you need it 🦋
  • 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). insert before, literally same energy 💜
  • 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". dependency lore, all in one argument 🫶
  • 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 are duplicates, count is the girlies' tiebreaker 👑
  • 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. keep the original timestamp or get the extraction timestamp, your call ⏰
  • O — Display member offsets inside the archive. Use together with the t option. offset reveal, but only with t 💅
  • 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
ar rcST archive.a subdir/file1 subdir/file2 file1

...will result in that first subdir/file1 getting replaced by file1 from the current directory. Slap a P in there and that replacement does not happen. no cap 💅

  • 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 all by itself. Running ar s on an archive is exactly the same as running ranlib on it. same energy, different outfit ✨
  • S — do not generate an archive symbol table. This can speed things up when you're building a big library in several steps, ngl, but it'll negatively impact performance if the resulting archive gets used with the linker. So to actually get a symbol table, you gotta either leave S off on the last time you run ar, or run ranlib on the archive afterwards. 🫶
  • T — deprecated alias for --thin. Big disclaimer bestie: T is not recommended, because in a bunch of other ar implementations T means something totally different — as specified by X/Open System Interface. messy. 💀
  • u — okay so normally ar r... inserts all the files you list. If you only want to insert the ones that are newer than existing members with the same names, use this modifier. The u modifier is only allowed for the r (replace) operation. In particular, qu is not allowed, because checking timestamps would lose the speed advantage you get from q.
Heads up 🎀 — if an archive was created in a deterministic manner, e.g. via the D modifier, then replacement will always happen and the u modifier is completely ineffective.
  • U — do not operate in deterministic mode. This is the exact 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 — asks for the verbose version of an operation. Lots of operations print extra info, like the filenames being processed, when you tack v on the end. iconic behavior honestly 👑
  • V — shows the version number of ar. that's it. that's the whole modifier. ✨

The ar program also supports some command-line options which are neither modifiers nor actions, but which do change its behaviour in specific ways:

  • --help — displays the list of command-line options supported by ar, then dips out. bye 👋
  • --version — displays the version information of ar, then exits. cute and short 🎀
  • -X32_64 — ar ignores an initial option spelled -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. so if you came here expecting the other -X flags... nope 🙈
  • --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 isn't 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 gets used. first come, first served bestie ✨

Please note: 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's called LLVMgold.so. The GCC plugin is always backwards compatible with earlier versions, so it's 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
not me leaving this exactly how the page has it 💀 the original sentence just stops at "See" — I'm not out here inventing lore, bestie.
  • --output dirname — --output lets you specify a path to a directory that archive members should be extracted into. If you don't specify this option, the current directory gets used. 🍓
Note — even though this option's presence implies an x extraction operation, you still have to actually include that option on the command line. can't just vibe your way into it, sorry 😭
  • --record-libdeps libdeps — --record-libdeps is identical to the l modifier, just handled in long form. same thing, longer name 💅
  • --thin — makes 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 that get read are inserted in place of the original @file option. If file doesn't exist, or can't be read, then the option is treated literally, and not removed. 🧚

Options inside file are separated by whitespace. A whitespace character may be included in an option by wrapping the whole option in either single or double quotes. Any character (including a backslash) may be included by prefixing the character with a backslash. And yes — the file may itself contain additional @file options; any such options get processed recursively. it's giving inception, and we love her ⭐

👀 SEE ALSO

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

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".

that's the whole page, bestie ✨💖 this little masterpiece is binutils-2.47, dated 2026-08-31 — go forth and archive responsibly, mwah 🫶💅🎀

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