Finding arguments for variables

UNIX for Beginners Q & A
1

Hello, I've done considerable research but haven't been able to locate info on finding available arguments for variables, and really anything that doesn't come with an associated Man page.

For instance:

$RETURN_CODE -ne 0

Clearly "ne" stand for Not Equal, and likewise if I replaced it with "-eq" that would be Equal.

But I haven't found anywhere that lists out arguments for a given variable.

Can anyone help? Does such an argument repository even exist?

Thanks!

2

man test or man [ will cover cases where your script uses:

test $RETURN_CODE -ne 0

and:

[ $RETURN_CODE -ne 0 ]

For cases where your script uses:

[[ $RETURN_CODE -ne 0 ]]

you'll need to look at the man page for your shell (which will probably also cover test expression and [ expression ] in addition to [[ expression ]] ).

3

Don,

Thanks so much for the reply. Actually though, I found I didn't ask this question appropriately. The -ne and -eq in my example are comparison operators not arguments, and I found a list of operators online.

Thanks again!

4

Shouldn't the man page of your shell be the first choice before searching the net? man bash :

5

Hi.

I like Advanced Bash-Scripting Guide because it has tables and examples.

Best wishes ... cheers, drl