[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: `if $(cmd);' is a positive when there's no output from cmd
From: |
Herculano Einloft |
Subject: |
Re: `if $(cmd);' is a positive when there's no output from cmd |
Date: |
Sun, 16 Apr 2006 00:04:05 -0300 |
Em (02:25:11), Andreas Schwab escreveu:
>Herculano Einloft writes:
>
>> Hey all,
>>
>> $ if $(echo string >/dev/null); then echo true; fi
>> true
>>
>> This should be a syntax error
>
>No, it is a perfectly valid command, syntactically. That the command
>substitution expands to nothing has no significance any more once the
>command is parsed, just like shell meta characters resulting from
>expansions are taken literally.
>
>Andreas.
>
Anyway, I see your point. It can't be a syntax error, since
of course it parses correctly.
It's kind of a weird case though, but I guess that's it.
Thanks all