Core utilities

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Core utilities are the basic, fundamental tools of a GNU/Linux system. This article provides an incomplete overview of them, links their documentation and describes useful alternatives. The scope of this article includes, but is not limited to, the GNU coreutils. Most core utilities are traditional Unix tools (see Heirloom) and many were standardized by POSIX but have been developed further to provide more features.

Most command-line interfaces are documented in man pages, utilities by the GNU Project are documented primarily in Info manuals, some shells provide a help command for shell builtin commands. Additionally most utilities print their usage when run with the --help flag.


The following table lists some important utilities which Arch Linux users should be familiar with. See also intro(1).

Package Utility Description Documentation Alternatives
shell built-ins cd change directory cd(1p) #cd alternatives
GNU coreutils ls list directory ls(1), info tree, #ls alternatives
cat concatenate files to stdout cat(1), info tac(1), #cat alternatives
mkdir make directory mkdir(1), info
rmdir remove empty directory rmdir(1), info
rm remove files or directories rm(1), info shred
cp copy files or directories cp(1), info #cp alternatives
mv move files or directories mv(1), info
ln make hard or symbolic links ln(1), info
chown change file owner and group chown(1), info chgrp(1)
chmod change file permissions chmod(1), info
dd convert and copy a file dd(1), info
df report file system disk space usage df(1), info #df alternatives
du estimate disk space used by files and directories du(1), info #du alternatives
GNU tar tar tar archiver tar(1), info archivers
GNU less less terminal pager less(1) terminal pagers
GNU findutils find search files or directories find(1), info, GregsWiki #find alternatives
GNU diffutils diff compare files line by line diff(1), info #diff alternatives
GNU grep grep print lines matching a pattern grep(1), info #grep alternatives
GNU sed sed stream editor sed(1), info, one-liners
GNU gawk awk pattern scanning and processing language gawk(1), info nawk, mawkAUR
util-linux dmesg print or control the kernel ring buffer dmesg(1) systemd journal
lsblk list block devices lsblk(8)
mount mount a filesystem mount(8)
umount unmount a filesystem umount(8)
su substitute user su(1) sudo, doas
kill terminate a process kill(1) pkill(1), killall(1)
procps-ng pgrep look up processes by name or attributes pgrep(1) pidof(1)
ps show information about processes ps(1) top(1), task managers
free display amount of free and used memory free(1)

Preventing data loss

rm, mv, cp and shell redirections happily delete or overwrite files without asking. rm, mv, and cp all support the -i flag to prompt the user before every removal / overwrite. Some users like to enable the -i flag by default using aliases. Relying upon these shell options can be dangerous, because you get used to them, resulting in potential data loss when you use another system or user that does not have them. The best way to prevent data loss is to create backups.


This table lists core utilities that often come in handy.

Package Utility Description Documentation Alternatives
shell built-ins alias define or display aliases alias(1p)
type print the type of a command type(1p) which(1)
time time a command time(1p)
GNU coreutils tee read stdin and write to stdout and files tee(1), info
mktemp make a temporary file or directory mktemp(1), info
cut print selected parts of lines cut(1), info
tr translate or delete characters tr(1), info
od dump files in octal and other formats od(1), info hexdump(1), vim's xxd(1)
sort sort lines sort(1), info
uniq report or omit repeated lines uniq(1), info
comm compare two sorted files line by line comm(1), info
head output the first part of files head(1), info
tail output the last part of files, or follow files tail(1), info
wc print newline, word and byte count wc(1), info
GNU binutils strings print printable characters in binary files strings(1), info stringsextAUR
GNU glibc iconv convert character encodings iconv(1) recode
file file guess file type file(1)

The moreutils package provides useful tools like sponge(1) that are missing from the GNU coreutils.


Alternative core utilities are provided by the following packages:

  • BusyBox — Utilities for rescue and embedded systems. || busybox
  • Toybox — An all-in-one Linux command line. || toyboxAUR
  • uutils — Cross-platform Rust rewrite of the GNU coreutils. || uutils-coreutils || heirloom-shAUR, heirloom-doctoolsAUR
  • 9base — A port of various original Plan9 tools to unix. || 9base
  • sbase — A suckless variant of the *nix core utilities. || sbase-gitAUR
  • ubase — An extension of the sbase utilities. || ubase-gitAUR

cat alternatives

  • bat — A cat clone with syntax highlighting and Git integration. || bat

cd alternatives

  • zoxide — A smart cd command that learns your habits, allowing you to navigate anywhere in just a few keystrokes. || zoxide
  • autojump — A faster way to navigate your filesystem from the command line. || autojumpAUR

See also Bash#Auto "cd" when entering just a path and Zsh#Remembering recent directories.

cp alternatives

Using rsync#As cp/mv alternative allows you to resume a failed transfer, to show the transfer status, to skip already existing files and to make sure of the destination files integrity using checksums.

ls alternatives

  • broot — A new way to see and navigate directory trees. || broot
  • clifm — A file manager that can list files like ls(1) would (plus icons and RGB colors support). || clifmAUR
  • exa — Another ls replacement with color support, tree view, git integration and other features. || exa
  • lsd — Modern ls with a lot of pretty colors and awesome icons. || lsd

find alternatives

  • fd — Simple, fast and user-friendly alternative to find. Ignores hidden and .gitignore'd files by default. || fd
  • mlocate — Merging locate/updatedb implementation. || mlocate
  • plocate — A much faster locate. || plocate

For graphical file searchers, see List of applications/Utilities#File searching.

diff alternatives

While diffutils does not provide a word-wise diff, several other programs do:

  • git diff can do a word diff with --color-words, using --no-index it can also be used for files outside of Git working trees.
  • cwdiff — A GNU wdiff wrapper that colorizes the output. || cwdiffAUR
  • git-delta — A syntax-highlighting pager for git, diff, and grep output. || git-delta
  • dwdiff — A word diff front-end for the diff program; supports colors. || dwdiff
  • icdiff — A colorized diff tool written in Python. "Improved color diff" is meant to supplement normal diff use. || icdiffAUR
  • wdiff — A wordwise implementation of GNU diff; does not support colors. || wdiff

See also List of applications/Utilities#Comparison, diff, merge.

grep alternatives

  • mgrep — A multiline grep. || mgrepAUR
  • pdfgrep — A tool to search text in PDF files. || pdfgrep
  • ripgrep-all — Search in plain text and also in PDFs, E-Books, Office documents, zip, tar.gz. || ripgrep-all

Code searchers

The following three tools aim to replace grep for code search. They do recursive search by default, skip binary files and respect .gitignore.

  • ack — A Perl-based grep replacement, aimed at programmers with large trees of heterogeneous source code. || ack
  • ripgrep (rg) — A search tool that combines the usability of ag with the raw speed of grep. || ripgrep
  • The Silver Searcher (ag) — Code searching tool similar to Ack, but faster. || the_silver_searcher
  • ugrep (ug) — Ultra fast grep with interactive TUI, fuzzy search, boolean queries, hexdumps and more. || ugrep

Interactive filters

  • fzf — General-purpose command-line fuzzy finder, powered by find by default. || fzf
  • fzy — A fast, simple fuzzy text selector with an advanced scoring algorithm. || fzy
  • peco — Simplistic interactive filtering tool. || peco
  • percol — Adds flavor of interactive filtering to the traditional pipe concept of the UNIX shell. || percolAUR
  • skim — Fuzzy finder written in Rust, similar to fzf. || skim

df alternatives

  • duf — A disk usage/free utility. || duf

du alternatives

  • dust — A more intuitive version of du in rust. || dust
  • ncdu — Simple ncurses disk usage analyzer. || ncdu
  • gdu — Disk usage analyzer with console interface written in Go. || gdu

See also List of applications/Utilities#Disk usage display.

See also