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Re: the '-n' conditional
From: |
Chet Ramey |
Subject: |
Re: the '-n' conditional |
Date: |
Tue, 5 Jun 2001 10:39:51 -0400 |
> Isn't
>
> [-n string]
>
> and
>
> [string]
>
> supposed to evaluate to exactly the same thing?
If `string' is not null.
> When I run the following script:
>
> #!/bin/sh
> if [ -n $1 ]
> then
> echo Foo
> fi
> # end of script
>
> it echoes "Foo" regardless of whether there's a first parameter or not.
If $1 evaluates to nothing, you're left with [ -n ], which is true. Look
at the Bash FAQ, question E1.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
( ``Discere est Dolere'' -- chet)
Chet Ramey, CWRU chet@po.CWRU.Edu http://cnswww.cns.cwru.edu/~chet/