• Basic Unix Commands

Environment Control

Command                     Description

cd d                         Change to directory d
mkdir d                      Create new directory d
rmdir d                      Remove directory d
mv f1 [f2...] d              Move file f to directory d
mv d1 d2                     Rename directory d1 as d2
passwd                       Change password
alias name1 name2            Create command alias (csh/tcsh)
alias name1="name2"          Create command alias (ksh/bash)
unalias name1[na2...]        Remove command alias na
ssh nd                       Login securely to remote node
exit                         End terminal session
setenv name v               Set env var to value v (csh/tcsh)
export name="v"              set environment variable to value v (ksh/bash)

Output, Communication, & Help

Command                     Description

lpr -P printer f            
  or 
lp -d printer f              Output file f to line printer
script  [f]                  Save terminal session to f
exit                         Stop saving terminal session
mailx username               Send mail to user
man name                     Unix manual entry for name

Process Control

Command                     Description

CTRL/c *                     Interrupt processes
CTRL/s *                     Stop screen scrolling
CTRL/q *                     Resume screen output
sleep n                      Sleep for n seconds
jobs                         Print list of jobs
kill %                       Kill job n
ps                           Print process status stats
kill  -9 n                   Remove process n
CTRL/z *                     Suspend current process
stop  %n                     Suspend background job n
cmmd&                        Run cmmd in background
bg  [%n]                     Resume background job n
fg  [%n]                     Resume foreground job n
exit                         Exit from shell

Environment Status

Command                     Description

ls  [d]  [f...]              List files in directory
ls -1  [f...]                List files in detail
alias  [name]                Display command aliases
printenv  [name]             Print environment values
quota                        Display disk quota
date                         Print date & time
who                          List logged in users
whoami                       Display current user
finger  [username]           Output user information
chfn                         Change finger information
pwd                          Print working directory
history                      Display recent commands
! n                          Submit recent command n

File Manipulation

Command                     Description

vi  [f]                      Vi fullscreen editor
emacs  [f]                   Emacs fullscreen editor
ed  [f]                      Text editor
wc  f                        Line, word, & char count
cat  f                       List contents of file
more  f                      List file contents by screen
cat f1 f2 >f3                Concatenates f1 & f2 into f3
chmod mode f                 Change protection mode of f
cmp f1 f2                    Compare two files
cp f1 f2                     Copy file f1 into f2
sort f                       Alphabetically sort f
split  [-n]  f               Split f into n-line pieces
mv f1  f2                    Rename file f1 as f2
rm f                         Delete (remove) file f
grep 'ptn'  f                Outputs lines that match ptn
diff f1 f2                   Lists file differences
head f                       Output beginning of f
tail f                       Output end of f

Compiler

Command                     Description

cc  [-o f1]  f2              C compiler
lint f                       Check C code for errors
f77  [-o f1] f2              Fortran77 compiler
pc  [-o f1]  f2              Pascal compiler

Working with NFS files

Files saved on the UITS central Unix computers Steel, the Parallel PC cluster, Solar/Lunar, and the Research SP are stored on the Network File Server (NFS). That means that your files are really on one disk, in directories named for the central Unix hosts on which you have accounts.

No matter which of these computers you are logged into, you can get to your files on any of the others. Here are the commands to use to get to any system directory from any other system:

  cd /N/u/username/PPPC/
  cd /N/u/username/Cobalt/
  cd /N/u/username/Solar/
  cd /N/u/username/Steel/
  cd /n/u/username/SP/

Be sure you use the capitalization just as you see above, and substitute your own username for "username".

For example, if Jessica Rabbit is logged into her account on Steel, and wants to get a file on her SP account, she would enter:

  cd /N/u/jrabbit/SP/

Now when she lists her files, she'll see her SP files, even though she's actually logged into Steel.

You can use the ordinary Unix commands to move files, copy files, or make symbolic links between files. For example, if Jessica Rabbit wanted to move "file1" from her Steel directory to her SP directory, she would enter:

  mv -i /N/u/jrabbit/Steel/file1 /N/u/jrabbit/SP/

This shared file system means that you can access, for example, your SP files even when you are logged into Steel, and vice versa. However, if you are logged into the SP, you can only use the software installed on SP -- only users' directories are linked together, not system directories.

Abbreviations used in this document

CTRL/x       hold down control key and press x
d            directory
env          environment
f            filename
n            number
nd           computer node
prtr         printer
ptn          pattern
var          variable
[y/n]        yes or no
[]          optional arg
...         list