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Unix commands

Note that there are thousands of commands available on a typical unix box. In bash, just hit the "Tab" key twice and say yes, to display the the commands currently available on your machine. A standard unix operating system lists currently thousands of commands. Type x to list all commands starting with x. The following list contains some of the more frequently used programs.

Access Control

exit - terminate a shell (see "man sh" or "man csh")
logout - sign off; end session (C shell and bash shell only;)
passwd - change login password
rlogin - log in remotely to another UNIX system
ssh - secure shell
slogin - secure version of rlogin
yppasswd - change login password in yellow pages


mail - send and receive mail
mesg - permit or deny terminal messages and talk requests
pine - send and receive mail 
talk - talk to another logged-in user
write - write to another logged-in user

Programming Tools

as - assembler, specific to each machine architecture
awk - pattern scanning and processing language
bc - online calculator
cc - C compiler 
csh - C shell command interpreter
dbx - source-level debugging program
f77 - Fortran compiler 
gdb - GNU Project debugger
gprof - display profile of called routines
kill - kill a process
ld - the UNIX loader
lex - generate lexical analysis programs
lint - check C source code
make - maintain large programs
maple - symbolic mathematics program
math - symbolic mathematics program
nice - run a command at low priority (see "man nice" or "man csh")
nohup - run a command immune to hangups
pc - Pascal compiler (xlp on ADS)
perl - Popular script interpreter
prof - display profile data
python - Python programming language
sh - Bourne shell command interpreter
yacc - generate input parsing programs
xcalc - graphical calulator under x


apropos - locate commands by keyword lookup
find - locate file (i.e. find . -name *.tex -print)
info - start the info explorer program 
man - find manual information about commands
whatis - describe what a command is
whereis - locate source, binary, or man page for a program

emacs - screen-oriented text editor
pico - screen-oriented text editor (renamed called nano)
sed - stream-oriented text editor
vi - full-screen text editor
vim - full-screen text editor ("vi-improved")
File and Directory Management

cd - change working directory
chmod - change the protection of a file or directory
chown - change owner (or group) of a file or directory
chgrp - change group of a file or directory
cmp - compare two files
comm - select/reject lines common to two sorted files
cp - copy files
crypt - encrypt/decrypt files (CCWF only)
diff - compare the contents of two ASCII files
file - determine file type
grep - search a file for a pattern
gzip - compress or expand files
ln - make a link to a file
ls - list the contents of a directory
lsof - list of open files    
mkdir - create a directory
mv - move or rename files and directories
pwd - show the full pathname of your working directory
quota - display disk usage and limits
rm - delete (remove) files
rmdir - delete (remove) directories
stat - status of file (i.e. last access)
sync - flush filesystem buffers   
sort - sort or merge files
tar - create or extract archives
tee - copy input to standard output and other files
tr - translate characters
umask - change default file protections
uncompress - restore compressed file
uniq - report (or delete) repeated lines in a file
wc - count lines, words, and characters in a file

File Display and Printing

cat - show the contents of a file; catenate files
fold - fold long lines to fit output device
head - show first few lines of a file
lpq - examine the printer spooling queue
lpr - print a file
lprm - remove jobs from the printer spooling queue
more - display a file, one screen at a time
less - like more with more features 
page - like "more", but prints screens top to bottom
pr - paginate a file for printing
tail - show the last part of a file
zcat - display a compressed file
xv - show print, manipulate images
gv - show ps and pdf files
xpdf = shopw pdf files (use gv) 

File Transfer

ftp - transfer files between network hosts
rsync -  fast and flexible sync between computers
scp - secure version of rcp


alias - define synonym commands
chquota - change disk quota on ACITS UNIX systems
chsh - change default login shell
clear - clear terminal screen
echo - echo arguments
pbm - portable bitmap manipulation programs
popd - pop the directory stack (C shell only)
pushd - push directory on stack (C shell only)
script - make typescript of terminal session
setenv - set an environment variable (C shell only)
stty - set terminal options


netstat - show network status
rsh - run shell or command on another UNIX system
ssh - secure-shell version of rsh

Process Control

bg - put suspended process into background
fg - bring process into foreground
jobs - list processes
^y - suspend process at next input request
^z - suspend current process 

Status Information

clock - determine processor time
date - show date and time
df - summarize free disk space
du - summarize disk space used
env - display environment
finger - look up user information
history - list previously issued commands 
last - indicate last login of users
lpq - examine spool queue
manpath - show search path for man pages
printenv - print out environment
ps - show process status
pwd - print full pathname of working directory
set - set shell variables (C shell, bash, or ksh)
spend - lists year-to-date ACITS UNIX charges
stty - set terminal options
time - timing programs
top - list  top  cpu processes
uptime - show system load, how long system has been up
w - show who is on system, what command each job is executing
who - show who is logged onto the system
whois - Internet user name directory service
whoami - who owns the shell

Image Processing

gimp - photoshop type image processing program
xfig - drawing program
xv - image viewer
xvscan - scan picture 
xpaint - paint program
kpaint - kde paint program 


mplayer - mpg player 
realplay - realaudio player
timidity - midi to wav converter and player
xmms - mp3 player 

Text Processing

abiword - open source word processor
addbib - create or extend bibliographic database
col - filter reverse line feeds
diction - identify wordy sentences 
diffmk - mark differences between files
dvips - convert TeX DVI files into PostScript
explain - explain phrases found by diction program
grap - pic preprocessor for drawing graphs 
hyphen - find hyphenated words 
ispell - check spelling interactively
latex - format text in LaTeX (based on TeX)
pdfelatex - latex with pdf output 
latex2html - Latex to html
lookbib - find bibliography references
macref - make cross-reference listing of nroff/troff macro files
ndx - create a subject-page index for a document
neqn - format mathematics with nroff
nroff - format text for simple display
pic - make simple pictures for troff input
psdit - filter troff output for Apple LaserWriter
ptx - make permuted index (not on CCWF)
refer - insert references from bibliographic databases 
roffbib - run off bibliographic database 
sortbib - sort bibliographic database 
spell - find spelling errors
ispell - interactive spell checker
style - analyze surface characteristics of a document 
tbl - format tables for nroff/troff
tex - format text
tpic - convert pic source files into TeX commands 
wget -  grab webpage

X windows

grabmode - info on screen: i.e. "1152x864"  51.213kHz/56.59Hz
import - grab window (i.e. import ppm:- >out.ppm)
xdpyinfo -  number of colors 
xkill - kill xwindow
xlock - lock screen
xterm - xterminal
xwininfo - information on open window


html2ps - html to ps
latex2html - latex to html translator
lynx - text based webbrowser
netscape - webbrowser
sitecopy - sitecopy is for easily maintaining remote web sites.
weblint - html sytax and style checker