Check if time legal in tcsh....

Hi,

I want to verify that time is legal.
For example 23:00 = legal
25:00 = not legal.

When running the below code, of course I don't want to get the error message when time is not legal.

I tried to use the below but need you help since it's failed.

Quote:

if (`/bin/date -d "$arg" >& /dev/null` == "") then echo "\nError: Time $argv[1] not legal time" exit endif