Shell Commands

( in alphabetical order )

cd to change your current directory Go to your home directory

 cd ~

Go to a specified directory, e.g.

 cd /tmp

You can use

 cd -

to toggle between two directories with no effort at all.

find to search for files in a directory hierarchy

 find ./ -name param.inc

grep to show lines matching a pattern from files

 grep EPOT runs/mo-example/A.log
 grep -3 Stress runs/mo-example/A.log
 grep -w mea Fortran/MEAM-Baskes/meam/*

head to show the first several lines of the file

 head -n 20 runs/mo-example/A.log  #view the first 20 lines
 head -n -20 runs/mo-example/A.log #ignore the last 20 lines

nm to list symbols from object files

 nm Fortran/MEAM-Baskes/meam/linux/forces.o | grep phiid

sed to read the input file line by line

 sed  -n -e 10p -e 20p runs/mo-example/A.log #view the 10th and the 20th lines
 sed  -n 10, 20p runs/mo-example/A.log #view the lines from 10th to 20th   

tar the tar archiving utility

 tar -zxvf MD++.tar.gz
 tar -jxvf highlight-2.6.5.tar.bz2
 tar -cvzf foo.tar.gz foo
 tar -cvjf foo.tar.bz2 foo
 tar cvf MD++.tar MD++ --exclude MD++/runs --exclude MD++/scripts/work --exclude MD++/cookies --exclude ".svn"

$ tar --create --tape-length=2097152 --file=results-NACL2-1.tar results-NACL2
Prepare volume #2 for `results-NACL2-1.tar' and hit return: n results-NACL2-2.tar
Prepare volume #2 for `results-NACL2-2.tar' and hit return: 
Prepare volume #3 for `results-NACL2-2.tar' and hit return: n results-NACL2-3.tar
Prepare volume #3 for `results-NACL2-3.tar' and hit return: 
Prepare volume #4 for `results-NACL2-3.tar' and hit return: n results-NACL2-4.tar
Prepare volume #4 for `results-NACL2-4.tar' and hit return:

yum (Yellowdog Updater Modified) update program

 yum search gcc
 yum list installed | grep python-numeric
 yum remove python-numeric.i386
 yum install python-numeric.i386
 yum check-update gcc.i386
 yum update gcc.i386
 yum info gcc.i386

diff -b Can be used to compare two files when the tabbing and whitespace has been changed in a code (tabbing, blank lines, spaces, etc). Regular diff will state that 'a=b' is different than 'a = b'.