Bash Cheat Sheet

gistfile1.sh

-r file     #Check if file is readable.
-w file     #Check if file is writable.
-x file     #Check if we have execute access to file.
-f file     #Check if file is an ordinary file (not a directory, a device file, etc.)
-s file     #Check if file has size greater than 0.
-d file     #Check if file is a directory.
-e file     #Check if file exists.  Is true even if file is a directory.

if [ -f file ] ; then
  # File exists
fi

n1 -eq n2      #Check to see if n1 equals n2.
n1 -ne n2      #Check to see if n1 is not equal to n2.
n1 -lt n2      #Check to see if n1 < n2.
n1 -le n2      #Check to see if n1 <= n2.
n1 -gt n2      #Check to see if n1 > n2.
n1 -ge n2      #Check to see if n1 >= n2.

if [ $NUM -gt 2 ];
then
  #do something
fi