Advanced Unix Commands

ACCTCOM
See the commands of all users	acctcom | tail -20
See the commands of a particual user	acctcom -u | tail -20
Show entries for a specific commandpattern	acctcom -n | tail -20
Show all entries for commands staring with "l"	acctcom -n '^l' | tail -30
Swho the output in reverse order	acctom -b | more
AGREP
Find words with possible misspellings (here 2)	agrep -2 'macropperswan'
AT
Execute a command once in the future	at now + 5 days <>
AWK
Take first column of a file	awk '{print $1}'
Take first two colums inverted	awk '{print $2,"\t",$1}'
Print sum of first two colums	awk '{print $1 + $2}'
Find lines with "money" and print last column	awk '/money/ {print $NF}'
Find lines with "money" in second column	awk '$2 ~ /money/ {print $0}'
Find lines without "A" at end of 3-rd column	awk '$3 !~ /A$/ {print $0}'
For awk programming structures see separate page	Per Kistlers Awk page
BASH
Bourne again shell. Best interaktive shell right after zsh
BC
Calculate sin(5)	echo 's(5)' | bc -l
BG
Put last stopped job into the background	bg
BREAK
Leave the inermost loop (while/until/for)	break
CANCEL
Stop a print job allready started	cancel ( as found with lpstat -o)
CASE in ESAC
Selective structure in sh/bash/ksh
CC
Compile a file.c	cc -o
CHGRP
Change group of a file	chgrp
CHOWN
Change owner of a file	chown
CMP
Act on the difference of two files	cmp ||
COL
Printing the man pages without thousand "^H"	man | col -b |
CRONTAB
See your crontab file	crontab -l
Edit your crontab file	crontab -e
Every monday on 05:10 do /home/fred/foo.ksh	10 5 * * 1 /home/fred/foo.ksh
CRYPT
Encrypt a file with a password	crypt password <> cryptfile
Decrypt the above file	crypt password <> cleanfile
CSH
Oldest Berkly shell
CUT
Get the hostname field from the last output	last | cut -c11-40
DATE
Set the date (root only)	date
Special format of date (e.g. month only)	date +%m
DF
See the used space of the disks in kB	df -k
DIRCMP
Compare two directories	dircmp
DTKSH
dtksh is a ksh93 with X11 graphics	dtksh
DU
du = diskusage	du -ks
ED
Commandline editor. Only used if all else fails	ed
EGREP
Grep with "or"	egrep '(A|B)'
Exclude a and B	egrep -v '(A|B)'
EX
Edit a file from within a shell script	ex -s file <g/money/s//cash/ EOF
Edit a file with a script	ex -s file <>
EXPR
Calculate modulus	expr 10 % 7
Check for string in variable	expr $var : 'string'
Show first group of digits in string	expr $var : '[^0-9]*\([a-z]*\)'
FG
Put the last stopped job into the foreground	fg
FGREP
Find a string which is not a pattern	fgrep '*,/.()'
FILE
See the file type (e.g. ascii)	file
FIND
Find a file in the whole computer	find / -type f -name -print
Find a file pattern	find . -type f -name "**" -print
Delete all cores in the system	find / -type f -name core -exec /bin/rm -f {} \;
Find all files with a word in them	find . -type f -exec grep -l {} \;
Find files modified longer than a month ago	find . -type f -ctime +30 -print
Use found files more then once with xargs	find . -name "*.c" -print | xargs -i cp {} {}.bak
Don't search in nfs mounted filesystems	find . -local ...
Follow the links while searching	find . -follow ...
Look for files larger than 1 megabyte	find /path -size 1000000c -print
Run find but discard the "permission denied"'s	find ... 2>/dev/null ( in sh/bash/ksh only)
Find all manualpage directories	find / -type d -print | egrep '.*/(catman|man)$'
Find all directories with write permissions	find / -type d -perm -002 -print
GAWK
The gnu version of nawk
GREP
Find patterns in lines of files or stdin	grep '[a-z][0-9]'
Find lines without pattern	grep -v '^From'
Find files which contain a pattern	grep -l '^[cC]' *.f
Count lines with pattern	grep -c '[Ss]uccess'
Search while ignoreing case	grep -i 'lAbEgF'
Print a line number in front of the line	grep -n 'mo.*y'
HINV
Get infos about your host on silicon graphics	hinv -v
IF then else ENDIF
Branching structure in csh/tcsh
IF then else FI
Branching structure in sh/bash/ksh	if [[ condition ]];then commands;fi
KSH
Korn shell. (ksh88)	See Per Kistlers ksh script guide
KSH93
ksh93 with real number arithmetics	ksh93/ksh...depends on the system
LINE
Reprint lines until eof (sh/bash/ksh)	while line;do :;done
LN
Make a hard link b to file A	ln a B
Make a symbolik link b to file A	ln -s a B
Romove link B	rm B
LP
Print file on default printer	lp
Print file on specific printer	lp -d
LPSTAT
Show all printers	lpstat -a
Check the printer queue	lpstat -o
Show defoult printer destination	lpstat -d
Show printer status	lpstat -p
Show sceduler status	lpstat -r
MAKE
Make the first target of a makefile	make
Make a specific target of a makefile	make
Make according to another file than makefile	make -f
Just show what would be done but don't	make -n
MKDIR
Make a directory with subdirectories at once	mkdir -p //
MOUNT
See what is mounted	mount
See what is mounted, but formated	mount -p
Mount a cdrom to /cdrom	mount /dev/cdrom /cdrom
Mount a diskpartition to /usr	mount /dev/dsk/c0t3d0s5 /usr
NAWK
Enhanced version af awk
NL
Number text lines from a file	nl -bt -nln
NOHUP
Start a job imune to logouts	nohup &
OSVIEW
View system activity on SGI	osview
PACK
An old form of compress. Use gzip instead.	pack
PASSWD
Change your password	passwd
Delete password of a user (as root)	passwd -d
Change password of a user (as root)	passwd
PASTE
Put single col files into one file with as many cols	paste >
PERL
Programming language which can also be used from the commandline or from ksh scripts. See Per Kitlers perl programing introduction: perl
PR
Format an ascii file for printing (76 lines)	pr -l76 -h"title"
Print page formated via vpp (ETH only)	pr -l76 -h"title" | vpp -des=rz -dev=printer
RCP
Copy a file from one computer to another	rcp :// ://
REGCMP
Compile a regexp from a file	regcmp
Entry in the file above (example)	varname "^[a-z].*[0-9.*$"
RESET
Reset the terminal after having messed it up	reset
RPCINFO
Get portinfo from	rpcinfo -p
RSH
Execute a command on a remote computer	rsh
RUSER
See who is logged in in the local network	rusers
RWHO
Like rusers, but mostly doesn't work
SCRIPT
This logges all which passes the screen	script
SED
Substitute a string in a file	sed -e 's/fred/john/g'
Substitute a pattern in a file	sed -e 's/[0-9]+/number/g'
Change all "X" to red in a html file	sed -e 's!X!X!g;
Rename files with suffix .suf1 to files with suffix .suf2
ls -1 | grep '\.suf1$' | sed -e 's/\(.*\.\)suf1/mv & \1suf2/' | sh
Change a to b but only on lines with C	sed -e '/C/s/A/B/' >
Delete all lines which contain "you owe me"	sed -e '/you owe me/d' >
Have many editing commands in a file	sed -f >
SH
Shell. The oldest AT&T shell, which is standard for universal shell scripts. Ksh is it's successor.
SHUTDOWN
Stop the system	shutdown -h now
SLEEP
Tell ashell script to pause for 10 seconds	sleep 10
SORT
Sort lines of a file alphabetically	sort
Sort lines of a file numerically	sort -n
Sort and reverse the order	sort -r
Sort and take only one of equal lines	sort -u
Show the used user ID's from /etc/passwd	sort +2n -t: /etc/passwd | cut -d: -f3
SPELL
Check for misspelled words in a file	spell
Check, but ignore words from okfile	spell +
SPLIT
Split a big file for putting on floppy	split -b1m
Put splitters together if their name starts with x	cat x* >
STRINGS
Read ascii strings from a binary file	strings
STTY
Show the terminal settings	stty -a
Change the deletions chatachter to "^H"	stty erase "^H"
Do no more show what is typed in scripts	stty -echo
Show the typeing again	stty echo
SU
Become root with own environment	su
Become root with root environment	su -
As root become another user	su
TAIL
Report certain lines from a growing file	tail -f | grep
TAR
Pack together a whole directory	tar cvf .tar
Unpack a tar file	tar xvf .tar
Unpack and untar a file with normal tar	gzip -dc .tar.gz | tar xvf -
Unpack and untar a file with gnutar	tar xzvf tar.gz
Set the tape variable in the .cshrc for tar	tape=/dev/rmt/0mbn
Put a dir onto the tape	tar cv
Retrieve the dir from the tape	tar xv
Retrieve only a single file from the tape	tar xv
Get table of contents from tape	tar t
Copy a directory with links and propper permissions
(cd fromdir && tar -cBf - . ) | ( cd todir && tar -xBf - )
TCSH
Good interaktive shell from Berkly. Only second to bash.
TEE
Put output on screen and append to file	who | tee -a >
TEST
Check for a file	test -a
Check for beeing root	test -O /usr/bin/su
Check for astrin beeing non null	test -n "$foo"
Compare two strings numerically	test $var1 -gt $var2
In a ksh script one uses "test" indirectly	if [[ -a ]];then ...;fi
TIME
See how much time a command needs	time
TOUCH
Protect against the the crontab	find /myscratch -exec touch {} \;
TR
Replace a with x, b with y and c with z	tr '[a-c]' '[x-z]' <> outfile
TRAP
Catch "^C" etc. and execute a subroutine	trap "mysub;exit" 0 1 2 15
TRUE
Make a non extisting command to return 0	ln -s /usr/bin/true ranlib
TRUSS
See what system calls a command uses	truss > /dev/null
TYPSET
Show the functions which are active	typset
TTY
See the device for your terminal	tty
ULIMIT
Show the max file size you can write	ulimit
UMASK
Show your umask for new files	umask
Set a save umask	umask 077
UNIQ
Find a line of each equal ones an say how many	sort | uniq -c
Find uniq lines	sort | uniq -u
UPTIME
Show how long the computer is running	uptime
UUENCODE
Encode a file for mailing	uuencode decodedname namenow > codedname
UUDECODE
Decode a uuencoded file	uudecode
WAIT
Wait for a background job to terminate	wait $jobid
VI
The main unix editor	vi
A vi introduction on the net:	vi-www-page
WC
Count lines in a file	wc -l
XARGS
Execute a command for each line from pipe	| xargs grep 'pattern' {}
XON
Get an xterm from another computer	xon
Get anything from another computer	xon
ZSH
Inhanced ksh. But ksh93 and dtksh are now still better.