Listing and viewing files
| Command | Description |
| ls ls -l ls -a ls *.f ls data?.out ls [a-h]* ls ~ ls /usr/man/man1 cat myfile more myfile head myfile tail -20 myfile |
list the files in the current directory list protection, ownership, data and size list all files, including hidden files (i.e. .login) list all files ending with .f list all files with any character matching ? list all files beginning with letter a through h list the content of the home directory list the content of the directory /usr/man/man1 list the content (catenate) of the file myfile page the content of myfile, 'space' for next page, do 'man page' list the first 10 lines of myfile list the last 20 pages of myfile |
Using directories
| Command | Description |
| pwd mkdir work cd work cd work/quasar cd cd .. rmdir work |
list the name of the current working directory make a directory called work in the current directory move to work in the current directory move to the subdirectory work/quasar go back to the home directory (the top directory) move to the directory above the current directory remove the diectory work |
Manipulating files and directories
| Command | Description |
| cp file1 file2 cp /pub/recipes/src/rkqc.f . cp file ~ cp file mydir cp -r dir mydir cat file1 file2 > file3 rm myfile rm *.o rm -r mydir rm -f myfile mv file1 file2 mv file1 mydir |
copy the file named file1 to the file named file2 copy file rkqc.f in /pub/recipes/src to the current directory copy file named file to home directory copy file to the directory mydir copy the directory dir and everything in it to directory mydir concatenate (copy together) file1 and file2 on file3 remove file myfile (must be a file) remove all files ending with *.o remove directory mydir and its content remove file myfile, even when it is write-protected move (rename) file named file1 to file2 move file named file1 into directory mydir |
Editing files and controlling the terminal window
| Command | Description |
| vi myfile vi -r myfile emacs myfile setenv TERM vt100 stty erase ^H stty kill ^C stty all setenv DISPLAY neptun:0.0 |
edit the file myfile using the vi editor (find a vi manual) edit the file myfile after an abnormal termination using vi edit a file using the editor emacs (use the help option) set terminal emulation to vt100. Other options hp, xterm set backspace character to CTRL H (press this key) set kill character to CTRL C display all terminal settings set output screen to the display in front of you (see label) |
Remote logins, file transfer and shells
| Command | Description | |
| telnet origo rlogin origo rlogin origo -l vp3 hostname whoami logout or CTRL D exit ftp da601.ifa.au.dk rcp origo:mydir/myfile . rcp myfile origo:mydir rsh origo uptime |
log into the host origo remote login to origo. Terminal information passed and display. A line should be present in the .rhosts file on the host giving your user name and the host you come from to avoid the need for a password. login under the name vp3 on origo display the name of the current host display the current username logout from the current host exit from your current shell (command session) perform file transfer between your curent host and da601 remote copy of the file file in mydir on origo to current directory. .rhost file must contain proper permisions. remote copy the opposite direction run a remote shell (session) on origo. .rhost must be correct |
Passwords, permissions and ownership
| Command | Description |
| passwd chmod u+x my.exe chmod ugo+r myfile chmod u+rwx myfile chmod go-rwx myfil chmod ugo-w myfile chmod -R go-rwx mydir chown vp6 myfile chown -R vp3 mydir |
change your password change the mode of file my.exe to make it executable allow myfile to be read by user, group and others make myfile readable, writeable and executable make myfile accessible only to myself prevent any writing to or deletion of myfile make mydir and its content accessible only to me change owner for file myfile to vp6 change owner of the whole directory mydir to vp3 |
Using pipes, redirection and subshells
| Command | Description |
| ls -l | more ls -l | cat -n > ls_out prog.exe < prog.in > prog.out >& prog.err prog.exe >> prog.out cat prog.in -| prog.exe (date; prog.exe >& prog.out; date) > prog.log |
list files in a directory, one page at a time. '|' is called a pipe list the files, number each line and write to file ls_out execute prog.exe. Take input from prog.in, write output to prog.out and error messages to prog.err append output to prog.out copy prog.in to the standard input of prog.exe. Then read the keyboard (-) write start/stop time to prog.log, output/errors to prog.out |
Printing (at this site)
| Command | Description |
| lpr -Phpnew myfile lpr -Phplj4 myfile lpr -Phpcol myfile lpq -Phpnew lprm -Phpnew 23 a2ps -Phplj4 myfile |
print file myfile (postscript) on both side of paper print file (postscript) on one page only print file (postscript) on color printer list print queue remove job 23 (see lpq output) from print queue print ASCII file (text file) single sided. |
Finding strings and files
| Command | Description |
| grep FUNCTION *.f find . -name "*.tex" -print find . -mtime -2 -print find . -name "*.f" -exec grep EXP {} \; |
look for the string FUNCTION in all files ending with *.f look for all files with names ending with .tex in current directory and below find all files that have been modified within the last two days find all occurences of the string EXP in *.f files here ('.') and below |
Compiling, executing and analysing
| Command | Description |
| cc -o prog.exe prog.c cc -c prog.c cc -lX11 -c prog.c *.o mylib.a cc -g -o prog.exe prog.c prog.exe time prog.exe nice prog.exe cvd prog.exe core ar cr mylib.a p1.o p2.o |
compile and link prog.c. The executable is prog.exe compile prog.c and place the object code in prog.o compile prog.c and link with object files and library compile with debug option -g run the executable prog.exe time the program prog.exe run prog.exe with low priority run the debugger (SGI only) cvd on prog.exe and the core dump create the archive (library) mylib.a with two object files |
Job control
| Command | Description |
| prog.exe & ps ps -ef kill -TERM 1342 kill -QUIT 1342 kill KILL 1342 renice -20 1342 ^Z bg fg |
start prog.exe in background list your processes display full list of all processes tell process 1342 to terminate tell process 1342 to terminate and create a core file for debugging tell process to stop immediately (last possibility) lower priority of job 1342 stop the current job start the job that was stopped as a background process start the job stopped as a foreground job |
Disk usage
| Command | Description |
| du du -s * df -k |
disk usage of current directory and subdirectories in kbytes total disk usage of files and directories display free disk space on all disks in kbytes |
Filtering files
| Command | Description |
| paste file1 file2 cat file | sed 's/E012//g' cat file | awk '{print $1+$2}' cat file | awk '{if ($1>1.5) print $0}' |
join corresponding lines from file1 and file2 remove every occurence of the string E012 from the file using the stream line editor sed print the sum of column 1 and 2 for the file using the program awk print all lines, where the first column is larger than 1.5 |
Finding out about commands
| Command | Description |
| man cc man 5 passwd man 3c intro whatis ls file ls whereis ls which ls |
display the manual page for the command cc give the manual page for passwd from section 5 (file formats) give the introductory page from section 3c (C library routines) give a brief introduction to all commands starting with ls display the file type of ls give the location of all files connected with ls display the executable started by the ls command |
Finding out about yourself and other users
| Command | Description |
| who grep `whoami` /etc/passwd finger hans@origo finger @origo |
find out who is logged on display your entry in the passwd table display information on users matching hans on the host origo find out who is logged onto the host origo |