Basic Shell Commandsh1

cat file1                    # list file1 to screen
cat file1 file2 file3 > outfile  # add files together into outfile
cat *.txt > outfile          # add all .txt files together
cat file1 file2 | grep fred  # pipe files

cp file1 file2               # copy file1 to file2
cp file1 directory           # copy file1 into directory
cp file1 file2 file3 … directory  # copy files into directory
cp -R dir1 dir2/            # copy dir1 into dir2 including subdirectories
cp -pR dir1 dir2/           # copy directory, preserving permissions

mv file1 file2               # rename file1 to file2
mv dir1 dir2                 # rename directory dir1 to dir2
mv file1 file2 file3 … directory  # move files into directory

rm file1                     # delete a file (use -i to ask whether sure)
rm -r dir1                   # delete a directory and everything in it (CARE!)
rm -rf dir1                  # like above, but don't ask if we have a -i alias

rmdir dirname                # delete empty directory

ls file                      # does the file exist?
ls -l file                   # show information about the file
ls *.txt                     # show all files ending in .txt
ls -lt                       # show information about all files in date order
ls -lrt                      # above reversed in order
ls -a                        # show all files including hidden files
ls dir                       # show contents of directory
ls -d dir                    # does the directory exist?
ls -p                        # adds meaning characters to ends of filenames
ls -R                        # show files also in subdirectories of directory
ls -1                        # show one file per line

cd                          # go to home directory
cd ~/papers                 # go to /home/user/papers
cd ~fred                    # go to /home/fred
cd dir                      # go to directory (relative)
cd /dir1/dir2/dir3…         # go to directory (absolute)
cd -                        # go to last directory you were in

pwd                         # show current working directory

grep "hi there" file1 file2 …  # look for 'hi there' in files
grep -i "hi there" filename    # ignore capitals in search
cat filename | grep "hi there"  # use pipe
grep -v "foo" filename         # list lines that do not include foo

more file                    # show file one screen at a time
grep 'frog' file | more     # Do it to output of other command

gtar cf out.tar dir1         # put contents of directory into out.tar
gtar czf out.tar.gz dir1     # write compressed tar, out.tar.gz
gtar tf in.tar               # list contents of in.tar
gtar tzf in.tar.gz           # list contents of compressed in.tar.gz
gtar xf in.tar               # extract contents of in.tar here
gtar xzf in.tar.gz           # extract compressed in.tar.gz
gtar xf in.tar file.txt …    # extract file.txt from in.tar

gzip file.fits               # compresses file.fits into file.fits.gz
gunzip file.fits.gz          # recovers original file.fits
gzip *.dat                   # compresses all .dat files into .dat.gz
gunzip *.dat.gz              # decompresses all .dat.gz files into .dat
program | gzip > out.gz      # compresses program output into out.gz
program | gunzip > out       # decompresses compressed program output

ps -u jss                    # list jss's processes
ps -f                        # list processes started here in full format
ps -AF                       # list all processes in extra full format
ps -A -l                     # list all processes in long format
ps -A | grep tcsh            # list all tcsh processes

kill 666                     # this sends a "nice" kill to the process
kill -KILL 666               # (or equivalently)
kill -9 666                  # which should really kill it!
kill -STOP 667               # pause (stop) process
kill -CONT 667               # unpause process

top                          # show top processes consuming CPU time
# Press 'q' to exit, 'k' to kill a process, 'r' to renice a process

nice +19 myjob1              # run at lowest priority
nice +8 myjob2               # run at lowish priority

date                         # shows current date

file temp_70.jpg
# Output: temp_70.jpg: JPEG image data, JFIF standard 1.01, resolution (DPI), 72 x 72

quota -v                     # show disk quota information

printenv MYVARIABLE          # print specific variable
printenv                     # print all variables

passwd                       # change your password

emacs foo.txt                # open file in emacs

nano filename                # open file in nano
# Warning: can introduce extra line breaks if screen is too narrow!

firefox                      # start Mozilla Firefox

gedit                        # start Gnome text editor

openoffice.org               # start OpenOffice

man man                      # get help on man
man grep                     # get help on grep
man -s1 sort                 # show documentation on sort in section 1

info gtar                    # documentation for gtar

lp file.ps                   # sends postscript file to the default printer
lp -dlp2 file.ps             # sends file to the printer lp2
lp -c file.ps                # copies file first, so you can delete it
lpstat -p lp2                # get status and list of jobs on lp2
cancel lp2–258               # cancel print job lp2–258

lpr -Plp2 file.ps            # send file.ps to lp2
lpq -Plp2                    # get list of jobs on lp2
lprm -Plp2 1234              # delete job 1234 on lp2

cc test1.c                   # compile test1.c to a.out
cc -O2 -o test2.prog test2.c # compile test2.c to test2.prog

latex document.tex           # convert tex file to dvi

logout                       # close current shell
exit                         # alternative to logout