GNU Tools and Libraries Reference

A comprehensive overview of various GNU tools and libraries, categorized for easy navigation.

What is GNU?

GNU is an operating system that is free software—that is, it respects users' freedom. The GNU operating system consists of GNU packages (programs specifically released by the GNU Project) as well as free software released by third parties. The development of GNU made it possible to use a computer without software that would trample your freedom.

Table of Contents

• Archiving
• Basics
• Compression
• Development
• Editors
• Email-software
• Encryption
• GNU libraries
• GNU organization
• Individual utilities
• Libraries
• Localization
• Network applications
• Programming
• Programming & development tools
• Software development
• Software libraries
• Texinfo documentation system
• Text creation and manipulation

Archiving

• Tar: Making tape (or disk) archives.

Basics

• Bash: The GNU Bourne-Again SHell.
• Common options: Common command-line options.
• Coreutils: Core GNU (file, text, shell) utilities.
• Date input formats: Date input formats.
• Ed: The GNU line editor.
• File permissions: Access modes.
• Finding files: Operating on files matching certain criteria.
• Inetutils: GNU networking utilities.

Compression

• Gzip: General (de)compression of files (lzw).

Development

• FFTW3: FFTW User's Manual.
• libffi: Portable foreign function interface library.

Editors

• nano: Small and friendly text editor.

Email-software

• The Mutt E-Mail Client: Text based mail reader.

Encryption

• Nettle: A low-level cryptographic library.

GNU libraries

• GMP: GNU Multiple Precision Arithmetic Library.
• Assuan: An IPC library for non-persistent servers.
• libgcrypt: Cryptographic function library.

GNU organization

• Maintaining Findutils: Maintaining GNU findutils.

Individual utilities

• Gawk Work Flow: Overview. Participating in ‘gawk’ development.
• addr2line: Convert addresses to file and line.
• ar: Create, modify, and extract from archives.
• arch: Print machine hardware name.
• awk: Text scanning and processing.
• b2sum: Print or check BLAKE2 digests.
• base32: Base32 encode/decode data.
• base64: Base64 encode/decode data.
• basename: Strip directory and suffix.
• basenc: Encoding/decoding of data.
• c++filt: Filter to demangle encoded C++ symbols.
• cat: Concatenate and write files.
• chcon: Change SELinux CTX of files.
• chgrp: Change file groups.
• chmod: Change access permissions.
• chown: Change file owners and groups.
• chroot: Specify the root directory.
• cksum: Print POSIX CRC checksum.
• cmp: Compare 2 files byte by byte.
• comm: Compare sorted files by line.
• cp: Copy files.
• csplit: Split by context.
• cut: Print selected parts of lines.
• cxxfilt: MS-DOS name for c++filt.
• date: Print/set system date and time.
• dd: Copy and convert a file.
• df: Report file system usage.
• diff: Compare 2 files line by line.
• diff3: Compare 3 files line by line.
• dir: List directories briefly.
• dircolors: Color setup for ls.
• dirname: Strip last file name component.
• dlltool: Create files needed to build and use DLLs.
• dnsdomainname: Show DNS domain name.
• du: Report file usage.
• echo: Print a line of text.
• elfedit: Update ELF header and property of ELF files.
• env: Modify the environment.
• expand: Convert tabs to spaces.
• expr: Evaluate expressions.
• factor: Print prime factors
• false: Do nothing, unsuccessfully.
• find: Finding and acting on files.
• fmt: Reformat paragraph text.
• fold: Wrap long input lines.
• ftp: FTP client.
• ftpd: FTP Daemon.
• groups: Print group names a user is in.
• gunzip: Decompression.
• gzexe: Compress executables.
• head: Output the first part of files.
• hostid: Print numeric host identifier.
• hostname: Print or set system name.
• id: Print user identity.
• ifconfig: Configure network interfaces.
• inetd: Internet super-server.
• install: Copy files and set attributes.
• join: Join lines on a common field.
• kill: Send a signal to processes.
• link: Make hard links between files.
• ln: Make links between files.
• locate: Finding files in a database.
• logger: Send messages to the system log.
• logname: Print current login name.
• ls: List directory contents.
• md5sum: Print or check MD5 digests.
• mkdir: Create directories.
• mkfifo: Create FIFOs (named pipes).
• mknod: Create special files.
• mktemp: Create temporary files.
• mv: Rename files.
• nice: Modify niceness.
• nl: Number lines and write files.
• nm: List symbols from object files.
• nohup: Immunize to hangups.
• nproc: Print the number of processors.
• numfmt: Reformat numbers.
• objcopy: Copy and translate object files.
• objdump: Display information from object files.
• od: Dump files in octal, etc.
• paste: Merge lines of files.
• patch: Apply a patch to a file.
• pathchk: Check file name portability.
• ping: Packets to network hosts.
• ping6: Packets to IPv6 network hosts.
• pinky: Print information about users.
• pr: Paginate or columnate files.
• printenv: Print environment variables.
• printf: Format and print data.
• ptx: Produce permuted indexes.
• pwd: Print working directory.
• ranlib: Generate index to archive contents.
• rcp: Remote copy
• readelf: Display the contents of ELF format files.
• readlink: Print referent of a symlink.
• realpath: Print resolved file names.
• rexecd: Remote execution server.
• rexec: Remote execution client.
• rlogin: Remote login.
• rlogind: Remote login server.
• rm: Remove files.
• rmdir: Remove empty directories.
• rsh: Remote shell.
• rshd: Remote shell server.
• runcon: Run in specified SELinux CTX.
• sdiff: Merge 2 files side-by-side.
• seq: Print numeric sequences
• sha1sum: Print or check SHA-1 digests.
• sha2: Print or check SHA-2 digests.
• shred: Remove files more securely.
• shuf: Shuffling text files.
• size: List section sizes and total size.
• sleep: Delay for a specified time.
• sort: Sort text files.
• split: Split into pieces.
• stat: Report file(system) status.
• stdbuf: Modify stdio buffering.
• strings: List printable strings from files.
• strip: Discard symbols.
• stty: Print/change terminal settings.
• sum: Print traditional checksum.
• sync: Sync files to stable storage.
• syslogd: Syslog server.
• tac: Reverse files.
• tail: Output the last part of files.
• talkd: Talk server.
• talk: Talk client.
• tar: Invoking GNU ‘tar’.
• tee: Redirect to multiple files.
• telnetd: Telnet server.
• telnet: User interface to TELNET.
• test: File/string tests.
• tftp: TFTP client.
• tftpd: TFTP server.
• timeout: Run with time limit.
• touch: Change file timestamps.
• tr: Translate characters.
• traceroute: Trace the route to a host.
• true: Do nothing, successfully.
• truncate: Shrink/extend size of a file.
• tsort: Topological sort.
• tty: Print terminal name.
• uname: Print system information.
• unexpand: Convert spaces to tabs.
• uniq: Uniquify files.
• unlink: Removal via unlink(2).
• updatedb: Building the locate database.
• uptime: Print uptime and load.
• users: Print current user names.
• uucpd: Unix to Unix Copy.
• vdir: List directories verbosely.
• wc: Line, word, and byte counts.
• who: Print who is logged in.
• whoami: Print effective user ID.
• whois: Whois user interface.
• windmc: Generator for Windows message resources.
• windres: Manipulate Windows resources.
• xargs: Operating on many files.
• yes: Print a string indefinitely.
• zcat: Decompression to stdout.
• zdiff: Compare compressed files.
• zforce: Force .gz extension on files.
• zgrep: Search compressed files.
• zmore: Decompression output by pages.

Libraries

• History: The GNU history library API.
• RLuserman: The GNU readline library User's Manual.
• Readline: The GNU readline library API.
• libgpg-error: Error codes and common code for GnuPG.

Localization

• idn2: Internationalized Domain Name (IDNA2008/TR46) conversion.

Network applications

• Wget: Non-interactive network downloader.
• awkinet: TCP/IP Internetworking With ‘gawk’.

Programming

• flex: Fast lexical analyzer generator (lex replacement).

Programming & development tools

• gdbm_dump: Dump the GDBM database into a flat file.
• gdbm_load: Load the database from a flat file.
• gdbmtool: Examine and modify a GDBM database.
• GDBM: The GNU database manager.

Software development

• As: The GNU assembler.
• Bfd: The Binary File Descriptor library.
• Binutils: The GNU binary utilities.
• CTF: The CTF file format.
• GNU libunistring: Unicode string library.
• Gas: The GNU assembler.
• Ld: The GNU linker.
• Ld-Internals: The GNU linker internals.
• Make: Remake files automatically.
• SFrame: The Simple Frame format.
• bison: GNU parser generator (Yacc replacement).
• gprof: Profiling your program’s execution

Software libraries

• libidn2: Internationalized domain names (IDNA2008/TR46) processing.
• mpfr: Multiple Precision Floating-Point Reliable Library.

Texinfo documentation system

• Texinfo: The GNU documentation format.

• info stand-alone: Read Info documents without Emacs.

• install-info: Update info/dir entries. ... (Previous Content) ...

• makeinfo: Translate Texinfo source.

• pdftexi2dvi: PDF output for Texinfo.

• pod2texi: Translate Perl Pod to Texinfo.

• texi2any: Translate Texinfo source.

• texi2any customization: Customizing texi2any output

• texi2any modules: Texinfo Perl modules used in texi2any

• texi2dvi: Print Texinfo documents.

• texi2pdf: PDF output for Texinfo.

• texindex: Sort Texinfo index files.

Text creation and manipulation

• Diffutils: Comparing and merging files.
• Gawk: A text scanning and processing language.
• Gawk Work Flow: Participating in ‘gawk’ development.
• M4: A powerful macro processor.
• grep: Print lines that match patterns.
• pm-gawk: Persistent memory version of gawk.
• sed: Stream EDitor.