Bash comparison expression cheat sheet.

bash_comparison_expression.txt

Author: Aaron R. Phalen | Twitter: @aaron_phalen | Email: [email protected]

BASH Compairson Expressions
===========================

Summary:
  A brief introduction to comparison expressions import Bourne Again Shell (BASH).

I. Check for the existence of a file [ -e filepath]
  Example: 
    if [ -e /home/aaron/sample.txt ]; then
        echo "sample.txt exists."
  OUTPUT: sample.txt exists
  
II. Check for the existence of a file and executable permissions [ -x filepath ]  
  Example:
    if [ -x /home/aaron/sample.txt ]; then
      echo "sample.txt exists and is executable."
  OUTPUT: sample.txt exists and is executable.
  
III. Check for the existence of a file that is a socket.
  Example:
    if [ -S /home/aaron/sample.txt ]; then
      echo "sample exists and is a socket."
    else
      echo "does not exist or is not a socket."
  OUTPUT: does not exist or is not a socket.