Shell Programming and Scripting

I want to check if a zip code is valid, using a variable that stores the zipcode. I am not sure how I would do this in a script. I know that simply checking for the numerical range of the number will not work, because '1' would be '00001' in zip code format. I know when I am in shell, I can use wildcards and ranges to find certain files. How would I do something similar in C shell scripting? This following code is my attempt of checking for correct zip code format.

Code:

if ( $zipcode == "[0-9][0-9][0-9][0-9][0-9]" ) then
    echo Zip code is in correct format

Code:

set zipcode=01234
test $zipcode="[0-9][0-9][0-9][0-9][0-9]" && echo Zip code is in correct format || echo NOK

Thanks. So it's not possible to check using the if statement?

Yes it is but that's your homework
My example show you a basic AND/OR concept.

How come my code in the OP does not work? Is there a different syntax I need for the condition of my if statement?

Hi.
My specific suggestion is to look in man csh for "==".

My general suggestion is to avoid csh for scripting if at all possible. I often use tcsh for interactive work, but I use the Bourne shell family for scripting. It makes life far easier for me. See Csh Programming Considered Harmful for details.

Best wishes ... cheers, drl