Useful UNIX Commands

8/8/2019 Useful UNIX Commands

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Useful UNIX Commands

Useful UNIX Commands

The following is a list of some of the more important and useful commands in Unix (specific to HPUX)

Remember that the man command can be used to find out the specific usage of any of these.

Essentials

logout- use this command when you are done, always

man - use the command `man command'to learn about a command.

Files and Directories

cd- change directory

pwd- print working directory (the directory you are in)

rmdir- remove directory (the directory must be empty)

mkdir- make a new directory

rm - remove a file or directory ls - list files

cp - copy a file

mv - move a file (destroys original)

less - view a text file

cat- prints the contents of a file on the screen

touch - create an empty file

gzip and gunzip - compression and decompression

tar- Tape Archive. Now used to store directory trees as a single file for easy transfer. See the -xvf

and -cvf options in the man page

uudecode and uuencode decode and encode binary files as text files for transfers

System Status

date - displays the current date and time

du - displays amount of disk space in 512byte blocks ('du -s' gives the summary for a directory)

quota -v - displays disk limits and amount currently in use

ps - display running processes ('ps -ef | grep username' gives all the processes owned by aparticular user)

who - display who is on the machine and where they are connected from

w - display who is on and what they are doing

who - display who is on and where they are on from

jobs - display the jobs you own

uptime - display time, number of users, and load averages

loads - a local script to show the loads on all the HP700s

renice - alters priority of a running process. You should renice long simulations so you don't hog

processor cycles.

Networking

ssh - open an encrypted connection with a host

telnet- open a remote session with host

rlogin - open a remote session with host


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ftp - File Transfer Protocol: send and receive files betweem machines

ping- check to make sure a remote machine is reachable

finger- show information about a person on a system or whoever is on the remote system WWW

version

Editors and Text Processors

vi - Visual Editor. Great stuff

pico - Easy to use editor

grep - searches a file for a pattern

a2ps - (not currently availible) allows the formatting of text into a multi-columned format

Printing

Please seethe printing one-pagerfor details about printing.

lp - print the specified file. Common usage: 'lp -dhpps file.ps'

lpstat- tells you infomation about current print jobs

cancel- cancel a print job. Common usage: 'cancel hpps-###'

That should be a good start on the commands that you need. Take a look at the software available on the

700s as well. Remember, if you don't know, ask questions. Most people here in ECE are willing to help

other people.

Common UNIX Commands

This document presents a brief description of commonly used UNIX commands. The list is a small subset

of the available commands and utilities. For more information on these commands and others not listed

here, consult the online manual pages (see themancommand) which are accessible from WWW through

ourman pages gatewayor talk to a member of the Informatics Core staff.Note: Enter the commands below exactly as shown (including spaces and upper- or lowercase). Arguments

or parameters to the commands are shown in italics and should be replaced with your own values at the

time that you execute the command (e.g. the name of a file is an argument to thecat command rather than

the word,file).

aliasalias-termcommand-string

The alias built-in shell command allows the entering of shorter or easy-to-remember names to

execute longer or hard-to-remember commands. The command is entered to set alias-term equalto command-string. Ifcommand-stringhas spaces in it, single quotes should be around the string.For example, entering alias dir 'ls -al' will allow ls -al to be executed whenever the dir command

is entered (thus easing the transition to UNIX for the MS-DOS users). Each user can put these

alias commands in their.cshrc file to have the aliases automatically set each time the user logs in.

Entering alias by itself will list all the aliases currently set for the user.

catfile

The cat command displays the contents of the file named byfile. If the file is large, all but the last

screenfull of lines will scroll off the screen too quickly to read. To display the file a screenful at a

time, use themore command.
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chdirdirectory

cddirectory

The chdir command moves you (changes yourcurrent working directory) to directory. Entering

cd without the directory argument will move you to yourhome directory.

Examples:cd /usr/hgp

moves you to the hgp directory inside of the usr directory.cd ..

moves you to theparent directory of your current directory.

chmodpermissionspath

The chmod command changes the access permission associated with a file or directory ("file" will

be used here to refer to either a file or a directory).

Each file has three types of access: read (r), write (w) and execute (x). In als -al file listing, theabbreviations appear in the columns on the left. To see the contents of a file, the file must have

read (r) permission. To change the contents of a file (e.g. saving changes after editing), write (r)

permission must be enabled. To execute a command by entering the name at the UNIX prompt,

the file must have execute (x) permission. To access a directory, the execute (x) permission must

be granted for that directory. If a given type of access is not permitted, it will show up as a dash (-)

rather than r, w or x in the ls -al listing.

The access to a file can be controlled separately for three sets of users: the owner of the file (u), a

limited group of users (g), and everyone on the system (o). In a ls -al file listing, the first threecolumns (starting in column two of the listing) are the r, w and x access allowed for the owner, the

second three are the access allowed for the group and the third three are the access allowed foreveryone else.

Permissions can be specified in numeric format or using the abbreviations above. For the numeric

format, three numbers are specified where each number represents the access granted for one of

the three sets of users. Each permission number is determined by adding up the value associated

with each type of access: r = 4, w = 2 and x = 1. For example, the value 7 grants all access, the

value 5 grants only read and execute access but not write access and the value 0 does not allow

any access to the file. The numeric access specification is an absolute one; all three types of access

for all three sets of users are reset according to the newpermissions.Examples:

chmod 640 .cshrc

grants read and write permission (6) to the owner of the file, read-only permission to the group,and no permissions for everyone else. The would appear in a file listing as rw-r-----.

chmod 777 .

grants all access to the owner, group, and everyone for the current working directory.

Thepermissions can also be specified using abbreviations rather than numbers. Using this method,

some of the permissions can be changed without affecting others. Thepermissions format is . The + adds the access indicated to the file without affecting the other

permissions. The - removes the access from the file.

Examples:

chmod u+rw report

adds read and write permission to the file, report, for the owner of the file. Access for the group

and everyone is unchanged.

chmod +x somecommand

adds execute permission to the file, somecommand, for all three sets of users.chmod go-rwx private.file

removes all access to the file, private.file, for the group and everyone and leaves the owner'saccess unchanged.

chownusernamepath

The chown command changes the ownership of the file or directory,path, to user, username. Both

the user-ownership and the group-ownership may be changed at once by specifying user.group for

the username parameter. One must have root privilages to do this so this command will not be too

useful for most users. If you really want to own someone else's file that you have read-access to,

make a copy of the file using the command, cp.
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cpfile1 file2

The cp command creates an identical copy of the file,file1, and names the copy,file2. Note that

the ownership offile2 will be set to whoever does the cp command.

date

The date command displays the current date and time. Use date -u to see the time in GreenwichMean Time (GMT), universal time.

difffile1file2The diffcommand compares the contents of two text files and displays the differences. The lines

preceded with < are fromfile1. The lines preceded by > are fromfile2. Each section of differences

is separated by ---.

enscripttextfile

The enscript command converts the file, textfile, (that you might otherwise print with lpr) to

Postscript and then prints it. More importantly, enscript allows the printing of two text pagesreduced onto one piece of paper with page numbers and a title. For example, enscript -2rG

lots.of.docs prints the file, lots.of.docs, in landscape mode, two pages per printout, with fancy

headers.

exit

The exit command terminates the current UNIXshell. If you started this UNIX session (shell)

with either therlogin,su command from within another session, exit returns you to your previous

session. If not, exit usually just closes your window (either an xterm window or terminal program

window) or returns you to a login: prompt.fingername@address

The finger command displays information about user accounts with names (usernames or propernames) matching name on the machine identified by address. The argument name may be a

known username or a first or last proper name without any spaces although this varies from

machine to machine. When fingering @med.umich.edu, first and last name separated by a period

may be used, e.g. finger [email protected].

The finger command may not work if the remote machine is not a UNIX machine (although most

multi-user machines have finger capability these days). If only the @address portion of the

argument is used, all of the users currently logged into the remote machine may be displayed. If no

argument is specified, all of the users currently logged into your machine are shown (see also thewhocommand).

An electronic mail address can often be verified or determined using the finger command. For

example, finger [email protected] returns a list of all Johns, Johnsons, and other variationsin the UMMC network. finger [email protected] gives all the people with an a in their

first name and Smith in their last name.

greppatternfile

The grep command searches one or more files, specified byfile, for the text string specified by

pattern. For example, grep 'dna' seqfile1 will list all lines found in the file, seqfile1, whichcontain the text "dna". Grep is usually used to search for text in several files at once, e.g. grep

'dna' * will perform the same search on all the files in yourcurrent directory (see wildcard

charactersfor an explanation of*).

headfile

tailfile

The head and tail commands list the first (head) or last (tail) ten lines of your file. The number of

lines listed may be varied by including -n number-of-lines option. For example, head -n 50

report1 will list the first fifty lines of the file report1.hgppasswd

Seepasswd.killid-number

The kill command terminates theprocesswith the id, id-number. The process id can be

determined with theps command. Generally, the kill command is the last method tried to

terminate a running program. If a normal kill (a kill without any kill-level option specified before

the id-number) does not remove the process, including the -9 option will usually annihilate it

(unless it is azombie process -- in which case it doesn't exist so it can't be killed (confused yet?))

e.g. kill -9 18201 is a "sure kill" of process number 18201.
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lprtextfile

The lpr command will print the file, textfile on the default printer. A specific printer may be

specified with the -P option. For example, lpr -Phgp2 sequence sends the file, sequence, to the

printer named "hgp2".

HGP UNIX Special Case: We have two UNIX printers (whose name can be specified with the-Pname option of the print commands). Printerhgp1 is in 2570 MSRB II, and hgp2 is in 2568

MSRB II.lpq

The lpq command displays the status of jobs (documents) in the print queue (waiting to print). The

-Pprinteroption specifies which printer queue to check. For example, lpq -Phgp2 checks the

status of documents waiting to print on the printer named "hgp2".

lprmjob-number

The lprm command removes the waiting document,job-number, from the print queue. The valueforjob-numbercan be obtained from thelpq command. If the job is to be removed from a print

queue other than the default, the -Pprinterparameter is used to specify the print queue (just as

withlprand lpq). Note that each user may only remove print jobs that their own print jobs.

lspattern

The ls command lists the files and directories in a directory. Ifpattern is the name of a file, only

that file (orfiles ifwildcardsare used) is listed. Ifpattern is a directory name, the contents of that

directory are listed. Ifpattern is omitted, all the files and directories in yourcurrent directory are

listed. The output of the ls command may bepipedinto themore command to pause the listingafter each screenful of text (e.g. ls -al | more).

Here are a few of the options for the ls command (for a complete list, see thels man page):-a

lists allfiles in the current directory. Without this option, filenames that begin with a period (such

as .cshrc, .login, and ..) are not shown).

-l

lists the filenames in longformat. This format includes the protections (changable withchmod) on

each file and the owner of the file.

-g

adds thegroup ownership of the file to the information displayed with the -l option describedabove.

-F

highlights directories with a trailing /, executable files with a trailing * and symbolic links with atrailing @ in a listing.

Examples:

ls

lists every file (except those filenames that begin with a period) in in thecurrent directory.

ls -al /binlists all files in the /bin directory in the long format.

ls -laFg

lists all files in the current directory in long format (including group ownership), highlighting

directories, executable files and symbolic links.

mancommand

The man command displays the standard UNIX manual page for the commandyou specify. These

pages may be somewhat cryptic for some users but generally tell you all you would ever want to

know about the command. You may search our man pages now through ourman pages gateway.mddir1

mkdirdir1The mkdir command creates the directory, dir1, within yourcurrent directory (unless the

specification ofdir1 begins with a /).

HGP UNIX Special Case:md is analiasformkdir on our system.

morefile1

The more command displays the contents of the text file,file1, a screenful at a time, pausing at the

end of each screen until the user presses one of a few special keys. When the display pauses, the

user may press:
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to display to the next page of text,

to display only one more line of text,

/ followed by a wordand the to search for that wordin the remaining

text of the file,

? to see all the operations available in more,

q orCONTROL-C to quit displaying the file and return to the command

prompt.

more may also be used at the end of a "pipe"to cause the output from another command to be

paused a screen at a time. This is useful when a UNIX command produces a lot of output too fast

for the user to see before the output scrolls off the screen. For example, thels -alcommand often

produces long directory listings which are better viewed a screen at a time by entering ls -al |

more.mvname1name2

The mv command moves and/or renames the file or directory, name1. Ifname2 is an existing

directory, name1 will be moved (not copied) into the directory, name2. Ifname2 is not an existing

directory, name1 (whether it be a file or directory) will simply be renamed into name2. It is

possible to move andrename name1 at the same time ifname2 is a new name withing an existing

directory. Any file file already existing with name2 will be overwritten by the renaming or moving

ofname1 unless mv -i is used, which asks the user for confirmation of destruction of existing files.HGP UNIX Special Cases:mv is analias formv -i on the HGP systems so using the -i option isnot necessary unless mv has been unaliased or aliased to something new.

passwd

hgppasswd

The passwd command changes your UNIX login password. After entering the command passwd,

you will be asked to enter your old password, then the new password that you want to change to,

and then the same new password again. You are asked to enter the new password twice to assure

that you have typed it correctly. None of the passwords you enter will be displayed on the screen

as you type them.

HGP UNIX Special Cases:

The passwd command only affects your UNIX login password and does not

change your Sybase database login password. hgppasswd allows to to remotely set your passwd on

mendel.hgp.med.umich.edu without having to first login to that machine if you are

currently logged into another HGP Sun workstation. Why would you want to do this?

The passwords on mendel are copied out to all the other Suns twice a day. If you changed

your password on any machine other than mendel using the passwd command, it will beoverwritten with your password from mendel within twelve hours, effectively reverting

back to your old password. Therefore, any password changes must be made by running

the passwd command while logged into mendel (to log into mendel from any other HGP

Sun, see therlogincommand) or by using the hgppasswd command while logged into

any other machine. Note that running hgppasswd from a machine other than mendel does

not set your new password on your current machine immeadiately. You may additionally

run the passwd command on the local machine to make the change immeadiately for that

machine.

ps

The ps command displays a list of theprocesses currently running on the machine that you are

logged into. If no arguments are entered with the ps command, only the "important" processes,

that you own (i.e. that you are running) are displayed. The -a option includes processes owned by

others in the list. The -g option includes all processes, not just "important" processes. The -u

option provides more information for each processes than is printed by default.

Examples (note that the dash in a ps option is not required):
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ps g

List all the processes running that you own (minimal information).

ps ug

List all the processes running that you own (lots of information).

ps agList all the processes running on this machine no matter who owns them.

To terminate a process, see the kill command.pwd

The pwd command displays the fullpathof yourcurrent working directory. In other words, it tells

you what directory you are in.

rloginaddress

The rlogin command logs into another machine specified by address. The -l username option

allows you to specify a username to attempt the remote login with. If this option is omitted, yourcurrent username is used by default. Examples:

rlogin mendel logs you into the machine named mendel with your

current username

rlogin mendel -l smith logs you into the machine named mendel as user

smith (of course, you must know smith's

password).

You can close the connection from the remote machine by entering the command,exit.

rmyourfileThe rm command removes the file,yourfile, permanently from the filesystem. This cannot be

undone so be careful when using wildcards in the file specification. Use rm -i to force user-confirmation of each file to be removed. Using rm -rsomedirwill remove the subdirectory

somediras well as all the subdirectories and files within that subdirectory.

HGP UNIX Special Cases:rm is an aliasforrm -i on the HGP systems so using the -i option is

not necessary unless rm has been unaliased or aliased to something new.

rmdirdir1

The rmdir command deletes the empty subdirectory, dir1. To delete non-empty subdirectories,

seerm -r.

suusernameThe su command allows a user to assume the identity and permissions of another user, username

(provided that the password forusername is known). The su session is ending by entering the

command,exit.tailfile

See head.

telnetaddress

See telnetas listed in the glossary for now.

wcyourfileThe wc command counts the number of words or characters and lines in your file. If the -l option

is used, only the number of lines is counted.

who

The who command displays a list of who is logged on to the system and where they are logged on

from. See also finger.

Unix Command Summary

See the Unixtutorial for a leisurely, self-paced introduction on how to use the commands listed below. For

more documentation on a command, consult a good book, or use the man pages. For example, for more

information on grep, use the command man grep.

Contents

cat --- for creating and displaying short files
http://web.nwe.ufl.edu/writing/tools/unix/#killhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#pathhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#pathhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#pathhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#currentworkingdirectoryhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#currentworkingdirectoryhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#currentworkingdirectoryhttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/concepts.html#wildcardhttp://web.nwe.ufl.edu/writing/tools/unix/#aliashttp://web.nwe.ufl.edu/writing/tools/unix/#aliashttp://web.nwe.ufl.edu/writing/tools/unix/#rmhttp://web.nwe.ufl.edu/writing/tools/unix/#rmhttp://web.nwe.ufl.edu/writing/tools/unix/#rmhttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#headhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#telnethttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#telnethttp://web.nwe.ufl.edu/writing/tools/unix/#fingerhttp://www.math.utah.edu/computing/unix/unix-tutorial.htmlhttp://www.math.utah.edu/computing/unix/unix-tutorial.htmlhttp://www.math.utah.edu/computing/unix/#cathttp://web.nwe.ufl.edu/writing/tools/unix/#killhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#pathhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#currentworkingdirectoryhttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/concepts.html#wildcardhttp://web.nwe.ufl.edu/writing/tools/unix/#aliashttp://web.nwe.ufl.edu/writing/tools/unix/#rmhttp://web.nwe.ufl.edu/writing/tools/unix/#exithttp://web.nwe.ufl.edu/writing/tools/unix/#headhttp://web.nwe.ufl.edu/writing/tools/unix/glossary.html#telnethttp://web.nwe.ufl.edu/writing/tools/unix/#fingerhttp://www.math.utah.edu/computing/unix/unix-tutorial.htmlhttp://www.math.utah.edu/computing/unix/#cat


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chmod --- change permissions

cd --- change directory

cp --- for copying files

date --- display date

echo --- echo argument

ftp --- connect to a remote machine to download or upload files

grep --- search file head --- display first part of file

ls --- see what files you have

lpr--- standard print command (see alsoprint )

more --- use to read files

mkdir--- create directory

mv --- for moving and renaming files

ncftp --- especially good for downloading files via anonymousftp.

print --- custom print command (see also lpr)

pwd --- find out what directory you are in

rm --- remove a file

rmdir--- remove directory

rsh --- remote shell setenv --- set an environment variable

sort --- sort file

tail --- display last part of file

tar--- create an archive, add or extract files

telnet --- log in to another machine

wc --- count characters, words, lines

cat

This is one of the most flexible Unix commands. We can use to create, view and concatenate files. For our

first example we create a three-item English-Spanish dictionary in a file called "dict."% cat >dict

red rojo

green verde

blue azul

%

stands for "hold the control key down, then tap 'd'". The symbol > tells the computer that what

is typed is to be put into the file dict. To view a file we use cat in a different way:

% cat dict

red rojo

green verdeblue azul

%If we wish to add text to an existing file we do this:

% cat >>dict

white blanco

black negro

%

Now suppose that we have another file tmp that looks like this:

% cat tmpcat gato
http://www.math.utah.edu/computing/unix/#chmodhttp://www.math.utah.edu/computing/unix/#cdhttp://www.math.utah.edu/computing/unix/#cphttp://www.math.utah.edu/computing/unix/#datehttp://www.math.utah.edu/computing/unix/#echohttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#grephttp://www.math.utah.edu/computing/unix/#headhttp://www.math.utah.edu/computing/unix/#lshttp://www.math.utah.edu/computing/unix/#lprhttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#morehttp://www.math.utah.edu/computing/unix/#mkdirhttp://www.math.utah.edu/computing/unix/#mvhttp://www.math.utah.edu/computing/unix/#ncftphttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#lprhttp://www.math.utah.edu/computing/unix/#pwdhttp://www.math.utah.edu/computing/unix/#rmhttp://www.math.utah.edu/computing/unix/#rmdirhttp://www.math.utah.edu/computing/unix/#rshhttp://www.math.utah.edu/computing/unix/#setenvhttp://www.math.utah.edu/computing/unix/#sorthttp://www.math.utah.edu/computing/unix/#tailhttp://www.math.utah.edu/computing/unix/#tarhttp://www.math.utah.edu/computing/unix/#telnethttp://www.math.utah.edu/computing/unix/#wchttp://www.math.utah.edu/computing/unix/#chmodhttp://www.math.utah.edu/computing/unix/#cdhttp://www.math.utah.edu/computing/unix/#cphttp://www.math.utah.edu/computing/unix/#datehttp://www.math.utah.edu/computing/unix/#echohttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#grephttp://www.math.utah.edu/computing/unix/#headhttp://www.math.utah.edu/computing/unix/#lshttp://www.math.utah.edu/computing/unix/#lprhttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#morehttp://www.math.utah.edu/computing/unix/#mkdirhttp://www.math.utah.edu/computing/unix/#mvhttp://www.math.utah.edu/computing/unix/#ncftphttp://www.math.utah.edu/computing/unix/#ftphttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#lprhttp://www.math.utah.edu/computing/unix/#pwdhttp://www.math.utah.edu/computing/unix/#rmhttp://www.math.utah.edu/computing/unix/#rmdirhttp://www.math.utah.edu/computing/unix/#rshhttp://www.math.utah.edu/computing/unix/#setenvhttp://www.math.utah.edu/computing/unix/#sorthttp://www.math.utah.edu/computing/unix/#tailhttp://www.math.utah.edu/computing/unix/#tarhttp://www.math.utah.edu/computing/unix/#telnethttp://www.math.utah.edu/computing/unix/#wc


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dog perro

%

Then we can join dict and tmp like this:

% cat dict tmp >dict2

We could check the number of lines in the new file like this:% wc -l dict2

8The command wc counts things --- the number of characters, words, and line in a file.

chmod

This command is used to change the permissions of a file or directory. For example to make a file

essay.001 readable by everyone, we do this:

% chmod a+r essay.001

To make a file, e.g., a shell script mycommand executable, we do this

% chmod +x mycommand

Now we can run mycommand as a command.

To check the permissions of a file, use ls -l . For more information on chmod, use man chmod.

cd

Use cd to change directory. Usepwd to see what directory you are in.

% cd english

% pwd

% /u/ma/jeremy/english

% ls

novel poems

% cd novel

% pwd

% /u/ma/jeremy/english/novel

% lsch1 ch2 ch3 journal scrapbook

% cd ..% pwd

% /u/ma/jeremy/english

% cd poems

% cd

% /u/ma/jeremy

Jeremy began in his home directory, then went to his english subdirectory. He listed this directory usingls ,found that it contained two entries, both of which happen to be diretories. He cd'd to the diretory novel, and

found that he had gotten only as far as chapter 3 in his writing. Then he used cd .. to jump back one level. If

had wanted to jump back one level, then go to poems he could have said cd ../poems. Finally he used cd

with no argument to jump back to his home directory.

cp

Use cp to copy files or directories.

% cp foo foo.2

This makes a copy of the file foo.

% cp ~/poems/jabber .

This copies the file jabber in the directory poems to the current directory. The symbol "." stands for the

current directory. The symbol "~" stands for the home directory.

date
http://www.math.utah.edu/computing/unix/#wchttp://www.math.utah.edu/computing/unix/#pwdhttp://www.math.utah.edu/computing/unix/#lshttp://www.math.utah.edu/computing/unix/#lshttp://www.math.utah.edu/computing/unix/#wchttp://www.math.utah.edu/computing/unix/#pwdhttp://www.math.utah.edu/computing/unix/#ls


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Use this command to check the date and time.

% date

Fri Jan 6 08:52:42 MST 1995

echo

The echo command echoes its arguments. Here are some examples:% echo thisthis

% echo $EDITOR

/usr/local/bin/emacs

% echo $PRINTER

b129lab1

Things like PRINTER are so-called environment variables. This one stores the name of the default printer

--- the one that print jobs will go to unless you take some action to change things. The dollar sign before an

environment variable is needed to get the value in the variable. Try the following to verify this:

% echo PRINTER

PRINTER

ftp

Use ftp to connect to a remote machine, then upload or download files. See also: ncftp

Example 1: We'll connect to the machine fubar.net, then change director to mystuff, then download the file

homework11:

% ftp solitude

Connected to fubar.net.

220 fubar.net FTP server (Version wu-2.4(11) Mon Apr 18 17:26:33 MDT 1994) ready.

Name (solitude:carlson):jeremy

331 Password required for jeremy.

Password:

230 User jeremy logged in.ftp> cd mystuff

250 CWD command successful.ftp> get homework11

ftp> quit

Example 2: We'll connect to the machine fubar.net, then change director to mystuff, then upload the file

collected-letters:

% ftp solitude

Connected to fubar.net.220 fubar.net FTP server (Version wu-2.4(11) Mon Apr 18 17:26:33 MDT 1994) ready.

Name (solitude:carlson):jeremy

331 Password required for jeremy.

Password:

230 User jeremy logged in.

ftp> cd mystuff

250 CWD command successful.ftp> put collected-lettersftp> quit

The ftp program sends files in ascii (text) format unless you specify binary mode:

ftp> binary

ftp> put foo

ftp> ascii

ftp> get bar

The file foo was transferred in binary mode, the file bar was transferred in ascii mode.
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grep

Use this command to search for information in a file or files. For example, suppose that we have a file dict

whose contents arered rojo

green verde

blue azulwhite blanco

black negro

Then we can look up items in our file like this;

% grep red dict

red rojo% grep blanco dict

white blanco% grep brown dict

%

Notice that no output was returned by grep brown. This is because "brown" is not in our dictionary file.

Grep can also be combined with other commands. For example, if one had a file of phone numbers named

"ph", one entry per line, then the following command would give an alphabetical list of all persons whose

name contains the string "Fred".

% grep Fred ph | sort

Alpha, Fred: 333-6565Beta, Freddie: 656-0099

Frederickson, Molly: 444-0981

Gamma, Fred-George: 111-7676

Zeta, Frederick: 431-0987

The symbol "|" is called "pipe." It pipes the output of the grep command into the input of the sort

command.

For more information on grep, consult

% man grep

head

Use this command to look at the head of a file. For example,

% head essay.001displays the first 10 lines of the file essay.001 To see a specific number of lines, do this:

% head -20 essay.001

This displays the first 20 lines of the file.

ls

Use ls to see what files you have. Your files are kept in something called a directory.

% ls

foo letter2

foobar letter3

letter1 maple-assignment1%

Note that you have six files. There are some useful variants of the ls command:% ls l*

letter1 letter2 letter3

%

Note what happened: all the files whose name begins with "l" are listed. The asterisk (*) is the " wildcard"

character. It matches any string.


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lpr

This is the standard Unix command for printing a file. It stands for the ancient "line printer." See

% man lprfor information on how it works. Seeprint for information on our local intelligent print command.

mkdir

Use this command to create a directory.

% mkdir essays

To get "into" this directory, do

% cd essaysTo see what files are in essays, do this:

% ls

There shouldn't be any files there yet, since you just made it. To create files, seecat oremacs.

more

More is a command used to read text files. For example, we could do this:

% more poemsThe effect of this to let you read the file "poems ". It probably will not fit in one screen, so you need to

know how to "turn pages". Here are the basic commands:

q --- quit more

spacebar --- read next page

return key --- read next line

b --- go back one page

For still more information, use the command man more.

mv

Use this command to change the name of file and directories.

% mv foo foobar

The file that was named foo is now named foobar

ncftp

Use ncftp for anonymous ftp --- that means you don't have to have a password.

% ncftp ftp.fubar.net

Connected to ftp.fubar.net

> get jokes.txtThe file jokes.txt is downloaded from the machine ftp.fubar.net.

print

This is a moderately intelligent print command.

% print foo

% print notes.ps

% print manuscript.dviIn each case print does the right thing, regardless of whether the file is a text file (like foo ), a postcript file

(like notes.ps, or a dvi file (like manuscript.dvi. In these examples the file is printed on the default printer.

To see what this is, do
http://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/emacs.htmlhttp://www.math.utah.edu/computing/unix/emacs.htmlhttp://www.math.utah.edu/computing/unix/#printhttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/emacs.html


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% print

and read the message displayed. To print on a specific printer, do this:

% print foo jwb321

% print notes.ps jwb321

% print manuscript.dvi jwb321To change the default printer, do this:

% setenv PRINTER jwb321

pwd

Use this command to find out what directory you are working in.

% pwd

/u/ma/jeremy% cd homework

% pwd

/u/ma/jeremy/homework

% ls

assign-1 assign-2 assign-3

% cd

% pwd/u/ma/jeremy

%

Jeremy began by working in his "home" directory. Then hecd 'd into his homework subdirectory. Cd

means " change directory". He used pwd to check to make sure he was in the right place, then used ls to see

if all his homework files were there. (They were). Then he cd'd back to his home directory.

rm

Use rm to remove files from your directory.% rm foo

remove foo? y

% rm letter*

remove letter1? yremove letter2? y

remove letter3? n

%

The first command removed a single file. The second command was intended to remove all files beginningwith the string "letter." However, our user (Jeremy?) decided not to remove letter3.

rmdir

Use this command to remove a directory. For example, to remove a directory called "essays", do this:

% rmdir essays

A directory must be empty before it can be removed. To empty a directory, use rm.

rsh

Use this command if you want to work on a computer different from the one you are currently working on.

One reason to do this is that the remote machine might be faster. For example, the command

% rsh solitude

connects you to the machine solitude. This is one of our public workstations and is fairly fast.

See also:telnet
http://www.math.utah.edu/computing/unix/#cdhttp://www.math.utah.edu/computing/unix/#cdhttp://www.math.utah.edu/computing/unix/#rmhttp://www.math.utah.edu/computing/unix/#telnethttp://www.math.utah.edu/computing/unix/#telnethttp://www.math.utah.edu/computing/unix/#cdhttp://www.math.utah.edu/computing/unix/#rmhttp://www.math.utah.edu/computing/unix/#telnet


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setenv

% echo $PRINTER

labprinter% setenv PRINTER myprinter

% echo $PRINTER

myprinter

sort

Use this commmand to sort a file. For example, suppose we have a file dict with contents

red rojogreen verde

blue azul

white blanco

black negro

Then we can do this:

% sort dict

black negro

blue azulgreen verde

red rojo

white blanco

Here the output of sort went to the screen. To store the output in file we do this:

% sort dict >dict.sorted

You can check the contents of the file dict.sorted usingcat ,more , oremacs .

tail

Use this command to look at the tail of a file. For example,

% head essay.001

displays the last 10 lines of the file essay.001 To see a specific number of lines, do this:

% head -20 essay.001This displays the last 20 lines of the file.

tar

Use create compressed archives of directories and files, and also to extract directories and files from an

archive. Example:

% tar -tvzf foo.tar.gz

displays the file names in the compressed archive foo.tar.gz while

% tar -xvzf foo.tar.gz

extracts the files.

telnet

Use this command to log in to another machine from the machine you are currently working on. For

example, to log in to the machine "solitude", do this:

% telnet solitude

See also:rsh.

wc
http://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/#morehttp://www.math.utah.edu/computing/unix/#morehttp://www.math.utah.edu/computing/unix/emacs.htmlhttp://www.math.utah.edu/computing/unix/emacs.htmlhttp://www.math.utah.edu/computing/unix/#rshhttp://www.math.utah.edu/computing/unix/#rshhttp://www.math.utah.edu/computing/unix/#cathttp://www.math.utah.edu/computing/unix/#morehttp://www.math.utah.edu/computing/unix/emacs.htmlhttp://www.math.utah.edu/computing/unix/#rsh


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Use this command to count the number of characters, words, and lines in a file. Suppose, for example, that

we have a file dict with contents

red rojo

green verde

blue azulwhite blanco

black negroThen we can do this

% wc dict

5 10 56 tmp

This shows that dict has 5 lines, 10 words, and 56 characters.

The word count command has several options, as illustrated below:

% wc -l dict5 tmp

% wc -w dict

10 tmp

% wc -c dict

56 tmp

In this Document . . .

Command words and arguments in bold typeface are shown exactly as you type them. Note thatmost are in lowercase. They must be typed that way: UNIX treats uppercase letters as different

from their lowercase counterparts. For items shown in italics, substitute an appropriate value.

Type the punctuation shown, such as a hyphen or vertical bar.

Control characters, typed by holding down the CTRL key while typing the character, are shown by

the notation ^x, where x is the character.

You must finish all UNIX commands by pressing the RETURN key, which is not shown here.

Connecting and Logging In

Connecting from Another Computer

If you are using another computer on the campus network (UTnet) or on the Internet, and if that computer

has a telnet command, you can use it to connect to a UNIX host. If the other computer is also running

UNIX, you can connect using rlogin. If your computer offers ssh, the Secure SHell, you can also connectusing ssh orslogin.

Connecting through Telesys

You must have a modem and a computer, and your user number must be validated to use the Telesys dial-

up system.

If you use SLIP or PPP software provided in the UT Connect package, it will make the Telesys connection,

and you can use telnet to connect to a UNIX host.

Logging InFor your first login, your login name is the user number issued to you by ACITS, in lowercase. When the

UNIX system prompts you for a password, give the password originally issued for your user number, also

in lowercase.For your first login, a special program will prompt you for a new UNIX password, possibly for a new

UNIX login name, and for other initialization information. Then it will log you out. The login name you

choose must be unique: it cannot be used by anyone else on the system. It will also be part of your e-mail

address, so you should choose something appropriate.


16/25

Make up a password that is six or more characters long, mixing uppercase, lowercase, and numbers to

make it difficult for others to guess. This password is the only thing that keeps someone else from using

your account and having full access to your work.

The program may ask you to choose a login shell, which is a UNIX command interpreter. The C shell

(/bin/csh) is recommended. For this document, the C shell is assumed to be the command interpreter-unlessotherwise stated. The program will also prompt you for optional data to put into a database that other users

on the Internet can view. This includes such items as your name, office address, and phone number. PressRETURN to leave any item blank.

To add or change data in a later session, use the command:

chfn

Exceptions: For the UTS system, you must run chfn on the machine named curly.cc.utexas.edu. For theADS and CCWF systems, send your request to

http://www.utexas.edu/cc/help/remark/

The Shell's Prompt for Commands

After you log in, you will see a prompt from the shell. The C shell's prompt usually includes the hostmachine's name. When you see the shell prompt, such as ccwf.cc.utexas.edu%, you can issue UNIX

commands.

Logging Out

IMPORTANT: Don't just turn off the terminal or workstation or disconnect the phone, and do not abandon

a terminal or workstation that seems "locked up". When you are through with your UNIX session, log out

by typing:

logout or^d

If you see a new UNIX login prompt, press ^d again. If you see a new Telesys> prompt, type:

exit

If you can't get a response at all and are unable to log out, see "Killing a Detached or Runaway Job" in this

document.

Changing Your Password

To change your password, type the command:

passwd

You will be prompted for your old password, then for your new one (twice for confirmation). If the two

new passwords match, the change will take effect in about one hour. If they do not match or are otherwise

unacceptable, you will be prompted to try again. Neither the old nor new password will display on the

screen. Changing your password on UTS, which must be done on the machine named curly.cc.utexas.edu,

does not affect your password for Telesys, CCWF, ADS, UMBS, or any other system.

Correcting Typing Errors
http://www.utexas.edu/cc/help/remark/http://www.utexas.edu/cc/docs/#killjobhttp://www.utexas.edu/cc/help/remark/http://www.utexas.edu/cc/docs/#killjob


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To correct an error before you press the RETURN key:

Press either the DELETE or BACKSPACE key to back up over a character, depending on the

system.

Press ^w to back up over a word.

Type ^u to erase the entire line.

Special Characters

^c

Interrupts and aborts execution of the current process, which cannot be restarted.^z

Suspends a process (temporarily stops it by putting it in the "background") so that you can give other UNIXcommands. To resume the process, use fg (foreground) or%n, where n is the background job number. To

disable ^z (make it undefined), give the command:

stty susp u

Writes to the file named to the right of this symbol instead of to standard output. Thus:

cat myfile

displays contents of "myfile" at your terminal (standard output), but:

cat myfile > listout

copies it to file "listout" instead, overwriting and destroying any previous contents of the file "listout". (Inthe C shell, a priorset noclobber command prevents such destruction.)

>>

Appends output to the file named to the right of this symbol. Thus:

cat nextfile >> listout

appends a copy of "nextfile" to file "listout" instead of overwriting what is already in "listout".

|

Creates a "pipe" so that output from one program (on left) becomes input to the next one (on right). Thus:

ls | lpr -Pcom_lw

sends output from the ls (listing) program to the lpr (printing) program.

*

Matches zero or more characters in a filename. For example, A* matches A, AbC, ARGUE, African, etc.

?

Matches any single character in a filename. For example, A?C matches AAC, ABC, ACC, etc.


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\

Prevents the following character from being interpreted as special. For example, \* makes * an ordinary

character.

The shell performs filename matching and input/output redirection before calling any program that uses the

files.

Setting Your Terminal Type

Some programs must know what type of terminal you are using in order to process control characters

correctly. To identify your terminal to the C shell, give the command:

setenv TERM type

where type is the terminal type, such as vt100. Your terminal type should already be defined by

initialization files set up for you when you first used a particular ACITS UNIX system.

Getting Online Help

Online UNIX documentation consists of "man" (manual), pages that you can display or print by using theman program. For example, to display the man page for the rm (remove) program, type:

man rm

For information on the man program itself, type:

man man

The program pauses after displaying each screenful of text. Press the space bar to continue, or press q to

quit.

To print a man page, "pipe" the output of the man program to the ul program (for underline and boldface

removal, which some printers can't do) then pipe that output to the lpr program--like this:

man rm | ul-Tdumb | lpr -Pacwl_lw

This prints the rm man page on the laser printer at the Student Microcomputer Facility. If you don't know

which man page you need, type:

aproposkeyword

to get a list of man pages that contain keywordin their title lines.

On the ADS system, get additional online help by using the InfoExplorer program. Type info -h to getstarted.

Longer documents and frequently asked questions can be searched and displayed by using your Web

browser to connect to:

http://www.utexas.edu/cc/unix/

Files and Directories

A UNIX filename or directory name can contain up to 255 letters, digits, and punctuation characters (best

limited to period and underscore). To list names of files in your own directory, type:
http://www.utexas.edu/cc/unix/http://www.utexas.edu/cc/unix/


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ls

This will not list filenames that begin with a period, unless you include the -a (all) option, like this:

ls -a

Names of initialization files typically begin with a period. For example, the C shell executes commands in.login each time you log in, and those in .cshrc each time you start up the C shell. The initialization file for

the Bourne shell or the Korn shell is .profile.

Otherls options include:

-l

long form, gives file protections, size in bytes.-F

marks directory names with a slash, executable files with an asterisk.

To list a subset of your files, use special characters. For example, to list all filenames beginning with A,

use:

ls A*

For complete information about the ls command, see:man ls

Creating and Editing Files

To create and alter files on a UNIX system, use a text editor. The most common one is the vi editor. Its use

is described in Introduction to UNIX, CCUG-1. The pico editor is very easy to use, with an on-screen menu

of commands and built-in help.

Emacs is another popular editor. A summary of Emacs commands is in GNU Emacs Pocket Reference

List, CCRL-34, available free at the Help Desk.

NOTE: To use most editors, your terminal type will need to be defined. A definition of vt100 works in

most cases.

Displaying a File at Your Terminal

Use the cat (catenate) or more command to display files at your terminal. For example:

cat source1 source2

displays "source1" and "source2" in that order.

more testfile

displays "testfile", pausing after each screenful. Press the space bar to see each new screen.

Printing a File

To send files to a printer, use lpr. For example:

lpr -Pfacsmf_lw source1 source2

prints files "source1" and "source2" on a laser printer at the Student Microcomputer Facility (SMF) in the

Flawn Academic Center (FAC). For information about options, output devices, and locations, see:
http://www.utexas.edu/cc/docs/ccrl34.htmlhttp://www.utexas.edu/cc/docs/ccrl34.htmlhttp://www.utexas.edu/cc/docs/ccrl34.htmlhttp://www.utexas.edu/cc/docs/ccrl34.htmlhttp://www.utexas.edu/cc/docs/ccrl34.html


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man lpr andhttp://www.utexas.edu/cc/unix/print-service/

On ADS, use InfoExplorer. To learn how, type

info -h

Deleting a File

Use rm (remove) to delete files from your directory. For example:

rm trashfile

The -i (interactive) option to rm causes the system to request confirmation of each file deletion. This option

may prevent accidental deletions and is useful if you are removing several files, as in:

rm -i *file

To delete a file that starts with a hyphen, use

rm - file

Setting a Search Path

Your command search path is the sequence of directories the shell searches to find commands you issue.

For the C shell, to add a directory to the search path, use set path. For example:

set path=($path /usr/lang) ; rehash

adds /usr/lang to your current search path, $path. But this works only for the current login session. If you

want your path set as above for EVERY login session, put the set path command in your.login file.

Killing a Detached or Runaway Job

If your terminal gets disconnected from your job or if it "locks up", you can kill the detached processes this

way:

1. Log in again to the same machine (if need be, from another terminal) and type: tty (tells which

terminal line you are now using) ps -u username(username is your own username. This lists all

your running processes)

2. For lines that have "csh" in the COMMAND column and that have a terminal line in the TT

column different from your current terminal, look in the PID column for the process id number of

that C shell.

3. Send that C shell's process id (pid) a hangup signal:

kill -HUP pid

4. Repeat the ps -uusername command to make sure all unwanted processes are gone. If not, reissuethe kill command like this:

kill -9 pid

Running Programs

To compile a Fortran program using the UNIX FORTRAN-77 compiler, f77, type:
http://www.utexas.edu/cc/unix/print-service/http://www.utexas.edu/cc/unix/print-service/http://www.utexas.edu/cc/unix/print-service/


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f77file

wherefile is the name of the source file. On ADS, you can also use xlforxlf90. If the source filename ends

in .f it is taken to be a FORTRAN-77 program.To compile a Pascal program, type:

pc file

wherefile is the name of the Pascal source file, which normally has .p as its final two characters.

Exception: on ADS systems, use

xlpfile

To compile a C program, type:

ccfile

wherefile is the name of the C source file, normally having .c as its last two characters. On ADS systems,

you can also use xlc.To compile a C++ program with the GNU C++ compiler, type

g++ file

All of these compilers compile and load object code into executable files named a.out. To execute your

program, simply type:

a.out

If you get the message "a.out: Command not found", check to be sure that your command search path is set

correctly. Or you may be able to solve the problem by using the command:

./a.out

to specify your current working directory. To write object code to some file other than a.out, use the -ocompiler option, like this:

cc -o output

where outputis the name of your executable file. To compile only, use the -c option. In this case, the

compiled program is written to a file with the same name as the source file but with the final .f, .p, or.creplaced by .o; no loading or linking takes place.

NOTE: Programs compiled on one machine architecture will not run on another. For example, an a.out filecompiled on the CCWF system will not execute on UTS. To debug your C, Pascal, FORTRAN, and

assembly language programs, compile them with the -g option, then use an interactive debugging program.For information on available debugging programs, type:

apropos debug

For other compiler options, see the man pages forf77, PC, and cc. On UNIX systems running AIX, see the

man pages forxlf, xlc, and xlp.

To print a listing of your program, type:


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lpr -Psite -psourcefile

To include line numbers, use:

cat -nsourcefile | lpr -Psite -p

Summary of Useful Commands

The following commands are grouped alphabetically by function. Unless noted otherwise, each has a man

page describing it in full. Commands marked "C shell only" are described in the csh man page (except on

ADS systems, where you should use InfoExplorer for information).Access Control

exit - terminate a shell (see "man sh" or "man csh")

logout - sign off; end session (C shell and bash shell only; no man page)

passwd - change login password

rlogin - log in remotely to another UNIX system

slogin - secure version of rlogin

Communications

from - list senders of mail

Mail - send and receive mail

mesg - permit or deny terminal messages and talk requests

pine - send and receive mail (easiest for new users)

talk - talk to another logged-in user (full screen)

write - write to another logged-in user

Programming Tools

ar - archive and library maintainer

as - assembler, specific to each machine architectureawk - pattern scanning and processing language

CC - C++ compiler (cxx on UTS; xlC on ADS)

cc - C compiler (xlc on ADS)

crontab - maintain periodic taskscsh - C shell command interpreter

dbx - source-level debugging program

f77 - FORTRAN compiler (xlf on ADS)

g++ - GNU C++ compiler

gcc - GNU C compiler gdb - GNU Project debugger

gprof - display profile of called routines

kill - kill a process

ld - the UNIX loader

lex - generate lexical analysis programslint - check C source code

make - manage multipart program projects

maple - 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 interpreterprof - display profile data

ranlib - convert archives to random libraries


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sh - Bourne shell command interpreter

/bin/time - time a command

yacc - generate input parsing programs

Documentation

apropos - locate commands by keyword lookup/usr/bin/X11/dxbook - start the BookReader program (UTS only)

info - start the InfoExplorer program (ADS only)

man - find manual information about commands

whatis - describe what a command is

whereis - locate source, binary, or man page for a program

Editors

emacs - screen-oriented text editor

ex - line-oriented text editor

pico - simple, screen-oriented text editor (easiest for new users)

sed - stream-oriented text editor

vi - full-screen text editorvim - full-screen text editor ("vi-improved")

File and Directory Management

cd - change working directory

chmod - change the protection of a file or directory

chquota - change disk quota on ACITS UNIX systemscmp - compare two files

comm - select/reject lines common to two sorted filescompress - compress a file

cp - copy files

crypt - encrypt/decrypt files (not on ADS)

diff - compare the contents of two ASCII files

file - determine file type

grep - search a file for a pattern

ln - make a link to a file

ls - list the contents of a directorymkdir - 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

sort - sort or merge files

tee - copy input to standard output and other files

tr - translate charactersumask - 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


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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 queuemore - display a file, one screen at a time

page - like "more", but prints screens top to bottompr - paginate a file for printing

tail - show the last part of a file

zcat - display a compressed file

File Transfer

ftp - transfer files between network hosts

rcp - transfer files between networked UNIX hosts

scp - secure version of rcp

rz - receive files using ZMODEM protocol

sz - send files using ZMODEM protocol

Miscellaneous

alias - define synonym commands

chsh - change default login shell

clear - clear terminal screen

echo - echo arguments

learn - request computer-aided instruction (not on CCWF)

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

News/Networks

lynx - text-only Web browser for display terminals

netscape - Web browsernetstat - show network status (on UTS, /usr/sbin/netstat)

Pnews - submit USENET news articles

rlogin - login remotely on another UNIX system

slogin - secure version of rlogin

tin - read/post USENET news articles

trn - read/post USENET news articles

rsh - run shell or command on another UNIX system

ssh - secure-shell version of rsh

telnet - run Telnet to log in to remote host

Process Control

(The following commands function under the C shell, bash, and ksh. They do not have separate man

pages.)

bg - put suspended process into background

fg - bring process into foregroundjobs - list processes


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^y - suspend process at next input request

^z - suspend current process

Status Information

spend - lists year-to-date ACITS UNIX charges

date - show date and timedf - summarize free disk space

du - summarize disk space used

env - display current environment or run programs under modified environment

finger - look up user information

history - list previously issued commands (C shell, bash, and ksh only)

last - indicate last login of userslpq - examine spool queue

manpath - show search path for man pages

printenv - display environment

Ps - show process status

pwd - display full pathname of working directory

set - set shell variables (C shell, bash, and ksh only)

stty - set terminal optionsuptime - show system load, how long system has been upw - 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

Text Processing

checknr - check nroff/troff files

col - filter reverse line feedsdvips - convert TeX DVI files into PostScript

eqn - typeset mathematics with troff

ispell - check spelling interactively

macref - make cross-reference listing of nroff/troff macro filesneqn - format mathematics with nroff

nroff - format text for simple display

pic - make simple pictures for troff input

psdit - filter troff output for Postscript printerspell - find spelling errors

tbl - format tables for nroff/troff

troff - format

Documents

Useful UNIX Commands