If Command Options - Complete List

Here is the complete list of if command options 

a) For file related operations

-a FILE : True if FILE exists.

-b FILE : True if FILE exists and is a block-special file.

-c FILE : True if FILE exists and is a character-special file.

-d FILE : True if FILE exists and is a directory.

-e FILE : True if FILE exists.

-f FILE : True if FILE exists and is a regular file.

-g FILE : True if FILE exists and its SGID bit is set.

-h FILE : True if FILE exists and is a symbolic link.

-k FILE : True if FILE exists and its sticky bit is set.

-p FILE : True if FILE exists and is a named pipe (FIFO).

-r FILE : True if FILE exists and is readable.

-s FILE : True if FILE exists and has a size greater than zero.

-t FD : True if file descriptor FD is open and refers to a terminal.

-u FILE : True if FILE exists and its SUID (set user ID) bit is set.

-w FILE : True if FILE exists and is writable.

-x FILE : True if FILE exists and is executable.

-O FILE : True if FILE exists and is owned by the effective user ID.

-G FILE : True if FILE exists and is owned by the effective group ID.

-L FILE : True if FILE exists and is a symbolic link.

-N FILE : True if FILE exists and has been modified since it was last read.

-S FILE : True if FILE exists and is a socket.

b) For String Comparison

-z STRING : True of the length if "STRING" is zero.

-n STRING : or  STRING : True if the length of "STRING" is non-zero.

STRING1 == STRING2 : True if the strings are equal. 

STRING1 != STRING2 : True if the strings are not equal.

STRING1 < STRING2 : True if "STRING1" sorts before "STRING2" lexicographically in the current locale.

STRING1 > STRING2 : True if "STRING1" sorts after "STRING2" lexicographically in the current locale.

c) For Integer Comparison

Hope below examples clarify how to do integer comparison

if [ "$a" -eq "$b" ]

if [ "$a" -ne "$b" ]

if [ "$a" -gt "$b" ]

if [ "$a" -ge "$b" ]

if [ "$a" -lt "$b" ]

if [ "$a" -le "$b" ]

d) For Logical Operations

EXPR1 -a EXPR2 : True if both EXPR1 and EXPR2 are true.

EXPR1 -o EXPR2 : True if either EXPR1 or EXPR2 is true.