Re: Redirecting the output to input file

From: Måns Rullgård (mru_at_inprovide.com)
Date: 02/16/05 

Date: Wed, 16 Feb 2005 12:46:05 +0100

Kasper Dupont <kasperd@daimi.au.dk> writes:

> arun.kumar.varma@gmail.com wrote:
>>
>> In our environment, cat is not a built-in. It's the executable
>> /usr/bin/cat. So, still my doubt is not cleared.
>
> In that case I suggest you verify if the command "cat x > x"
> actually truncates the file. I guess it might truncate the
> file before calling cat, and by the time cat is called and
> print the error message the file has already been truncated.

The question is why cat even bothers to check. 

-- 
Måns Rullgård
mru@inprovide.com

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