Some handy bash conditional checks

bash_conditional_checks.txt

Integer comparison

-eq
-ne
-gt
-ge
-lt
-le


Things to check for in conditional

-z              - checks to see if a string is null (zero length)
-n              - checks to see if a string is not null

-a file         - file exists
-d file         - file is a directory
-f file         - file is a regular file
-r file         - You have read permission on file
-s file         - file exists and is not empty
-w file         - You have write permission on file
-x file         - You have execute permission on file
-O file         - You own file
-G file         - Your group ID is the same as that of file
file1 -nt file2 - file1 is newer than file2 (based on modification date)
file1 -ot file2 - file1 is older than file2