Unix Utilities

* marks built-in shell utilities which are documented in the Linux sh man page.

# marks non-susv4 utilities or other documentation.

	susv4	Linux	description
	ls	ls	list directory contents
*	cd	sh	change the working directory
	man	man	display system documentation
	pwd	pwd	return working directory name
	mkdir	mkdir	make directories
	rmdir	rmdir	remove directories
	rm	rm	remove directory entries
	mv	mv	move (rename) files
	cat	cat	concatenate and print files
	more	more	display files on a page-by-page basis
#		less	opposite of more
	head	head	copy the first part of files
	tail	tail	copy the last part of a file
#		nano	Nano's ANOther editor, an enhanced free Pico clone
#		gcc	GNU project C and C++ compiler
	make	make	maintain, update, and regenerate groups of programs
#		wget	non-interactive network downloader
#		unzip	list, test and extract compressed files in a ZIP archive
#		zip	package and compress (archive) files

	susv4	Linux	description
*	read	sh	read a line from standard input
	test	test	evaluate expression (also built-in sh)
	chmod	chmod	change the file modes
	comm	comm	select or reject lines common to two files
#		seq	print a sequence of numbers
	touch	touch	change file access and modification times
	wc	wc	word, line, and byte or character count
	diff	diff	compare two files line by line
	printf	printf	write formatted output
#		rev	reverse lines of a file or files

	susv4	Linux	description
	cmp	cmp	compare two files byte by byte
	tr	tr	translate characters
	paste	paste	merge corresponding or subsequent lines of files
#		shuf	generate random permutations
	tee	tee	duplicate standard input
	kill	kill	terminate or signal processes
#		signal	overview of signals
#		screen	screen manager with VT100/ANSI terminal emulation

Also see the shell Pattern Matching Notation and the susv4 chapter on Regular Expressions.

	susv4	Linux	description
	awk	awk	pattern scanning and processing language
	ed	ed	edit text
	expr	expr	evaluate arguments as an expression
	grep	grep	search a file for a pattern
#		regex	POSIX.2 regular expressions
	sed	sed	stream editor
	df	df	report free disk space
	ln	ln	link files
	ar	ar	create and maintain library archives
#		tar	save and restore tape or disk archives
#		cpio	copy files to and from archives
#		bzip2	a block-sorting file compressor
#		gzip	compress or expand files
	find	find	find files
	sort	sort	sort, merge, or sequence check text files
	uniq	uniq	report or filter out repeated lines in a file
	xargs	xargs	construct argument lists and invoke utility

	susv4	Linux	description
	chown	chown	change the file ownership
	dd	dd	convert and copy a file
#		ldd	print shared object dependencies
#	stat	stat	get file status - includes description of struct stat
#		stat(1)	display file or file system status
#	execlp	execlp	execute a file
#	fork	fork	create a child process
#	getpid	getpid	get the process ID
#	wait	wait	wait for process to change state
#	dup2	dup2	duplicate a file descriptor
#	pipe	pipe	create pipe
#		pipe(7)	overview of pipes and FIFOs
#		lscpu	display information about the CPU architecture
#		mpstat	report processors related statistics
	ps	ps	report process status
#		top	display processes
#		proc	process information pseudo-file system
	yacc	yacc	yet another compiler compiler
	lex	lex	generate programs for lexical tasks

	susv4	Linux	description
*	alias	sh	define or display aliases
	at	at	execute commands at a later time
	basename	basename	return non-directory portion of a pathname
	batch	batch	schedule commands to be executed in a batch queue
	bc	bc	arbitrary-precision arithmetic language
*	bg	sh	run jobs in the background
	c99	c99	compile standard C programs
	cal	cal	print a calendar
	chgrp	chgrp	change the file group ownership
	cksum	cksum	write file checksums and sizes
*	command	sh	execute a simple command
	cp	cp	copy files
	crontab	crontab	schedule periodic background work
	csplit	csplit	split files based on context
	cut	cut	cut out selected fields of each line of a file
	date	date	write the date and time
	dirname	dirname	return the directory portion of a pathname
	du	du	estimate file space usage
	echo	echo	write arguments to standard output (also built-in sh)
	env	env	set the environment for command invocation
*	eval	sh	construct command by concatenating arguments
	ex	ex	text editor
	expand	expand	convert tabs to spaces
	false	false	return false value
*	fc	sh	process the command history list
*	fg	sh	run jobs in the foreground
	file	file	determine file type
	fold	fold	filter for folding lines
	fuser	fuser	list process IDs of all processes that have one or more files open
	gencat	gencat	generate a formatted message catalog
	getconf	getconf	get configuration values
*	getopts	sh	parse utility options
*	hash	sh	remember or report utility locations
	iconv	iconv	codeset conversion
	id	id	return user identity
	ipcrm	ipcrm	remove an XSI message queue, semaphore set, or shared memory segment identifier
	ipcs	ipcs	report XSI interprocess communication facilities status
	join	join	relational database operator
	link	link	call link function
	locale	locale	get locale-specific information
	localedef	localedef	define locale environment
	logger	logger	log messages
	logname	logname	return the user's login name
	lp	lp	send files to a printer
	m4	m4	macro processor
	mesg	mesg	permit or deny messages
	mkfifo	mkfifo	make FIFO special files
	newgrp	newgrp	change to a new group
	nice	nice	invoke a utility with an altered nice value
	nl	nl	line numbering filter
	nm	nm	write the name list of an object file
	nohup	nohup	invoke a utility immune to hangups
	od	od	dump files in various formats
	patch	patch	apply changes to files
	pathchk	pathchk	check pathnames
	pr	pr	print files
	renice	renice	set nice values of running processes
	sh	sh	shell, the standard command language interpreter
	sleep	sleep	suspend execution for an interval
	split	split	split files into pieces
	strings	strings	find printable strings in files
	strip	strip	remove unnecessary information from strippable files
	stty	stty	set the options for a terminal
	tabs	tabs	set terminal tabs
	time	time	time a simple command
	tput	tput	change terminal characteristics
	true	true	return true value
	tsort	tsort	topological sort
	tty	tty	return user's terminal name
*	ulimit	sh	set or report file size limit
*	umask	sh	get or set the file mode creation mask
*	unalias	sh	remove alias definitions
	uname	uname	return system name
	uncompress	uncompress	expand compressed data
	unexpand	unexpand	convert spaces to tabs
	unlink	unlink	call the unlink function
	vi	vi	screen-oriented (visual) display editor
*	wait	sh	await process completion
	who	who	display who is on the system
#		whoami	print effective userid
#		w	show who is logged on and what they are doing
	write	write	write to another user
	zcat	zcat	expand and concatenate data
#		base64	base64 encode/decode data
#		openssl	OpenSSL command line tool
#		clear	clear the terminal screen
#		col	filter reverse line feeds from input
#		error	analyze and disperse compiler error messages
#		fmt	simple optimal text formatter
#		fortune	print a random, hopefully interesting, adage
#		gpg	OpenPGP encryption and signing tool
#		indent	reformat a C program
#		script	make typescript of terminal session
#		sha1sum	compute and check SHA1 message digest
#		stdbuf	run command with modified buffering
#		tac	concatenate and print files in reverse
#		which	locate a command
#		yes	output a string repeatedly until killed
#	clock_gettime	clock_gettime	clock and time functions
#	isatty	isatty	test for a terminal device
#	regcomp	regcomp	regcomp, regerror, regexec, regfree - regular expression matching
#	strftime	strftime	format date and time
#		time(7)	overview of time and timers
#		GNU	date input formats
#		urandom	kernel random number source devices
#	closedir	closedir	close a directory
#	ftw	ftw	file tree walk
#	opendir	opendir	open a directory
#	readdir	readdir	read a directory
#	scandir	scandir	scan a directory for matching entries
#	dlopen	dlopen	gain access to an executable object file (example)
#	dlsym	dlsym	obtain the address of a symbol from a dlopen object
#	dlclose	dlclose	close a dlopen object
#	dlerror	dlerror	get dynamic linking diagnostic information
#		mknod	make block or character special files
#	mknod	mknod	create a special or ordinary file
#	alarm	alarm	set an alarm clock for delivery of a signal
#	close	close	close a file descriptor
#	fdopen	fdopen	associate a stream with a file descriptor
#		dc	an arbitrary precision calculator
#		bc	arbitrary precision arithmetic language (SunOS-5)
#		dc	desk calculator (SunOS-5)

	susv4		description
	admin		create and administer SCCS files
	asa		interpret carriage-control characters
	cflow		generate a C-language flowgraph
	compress		compress data
	ctags		create a tags file
	cxref		generate a C-language program cross-reference table
	delta		make a delta (change) to an SCCS file
	fort77		FORTRAN compiler
	get		get a version of an SCCS file
	jobs		display status of jobs in the current session
	mailx		process messages
	pax		portable archive interchange
	prs		print an SCCS file
	qalter		alter batch job
	qdel		delete batch jobs
	qhold		hold batch jobs
	qmove		move batch jobs
	qmsg		send message to batch jobs
	qrerun		rerun batch jobs
	qrls		release batch jobs
	qselect		select batch jobs
	qsig		signal batch jobs
	qstat		show status of batch jobs
	qsub		submit a script
	rmdel		remove a delta from an SCCS file
	sact		print current SCCS file-editing activity
	sccs		front end for the SCCS subsystem
	talk		talk to another user
	type		write a description of command type
	unget		undo a previous get of an SCCS file
	uucp		system-to-system copy
	uudecode		decode a binary file
	uuencode		encode a binary file
	uustat		uucp status enquiry and job control
	uux		remote command execution
	val		validate SCCS files
	what		identify SCCS files