List of common file test operators used in shell scripts:

  • -e file: Check if file exists
  • -f file: Check if file exists and is a regular file
  • -d file: Check if file exists and is a directory
  • -s file: Check if file exists and has size greater than 0
  • -r file: Check if file exists and is readable
  • -w file: Check if file exists and is writable
  • -x file: Check if file exists and is executable
  • -p file: Check if file exists and is a named pipe (FIFO)

Check man test for more and details.