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Mail Archives: cygwin/2007/03/10/17:53:31

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Date: Sat, 10 Mar 2007 15:55:39 -0700
From: Eric Blake <ebb9 AT byu DOT net>
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To: cygwin AT cygwin DOT com
Subject: Re: bash process substitution "<(list)" possible bug
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According to Tom Rodman on 3/10/2007 8:14 AM:
>   ~ $ /tmp/foo <(echo ABC)
>   + test -s /proc/self/fd/63
>   + echo 1
> 
> The 'test -s "$file"' in the test run above should return 0.

How do you figure?  pipes are special file types, and st_size is
unspecified in a stat() call on a pipe, so the -s test is unreliable in
the first place.  Not to mention there is an inherent race in your script
(did the 'echo ABC' process run before or after the 'test -s
/proc/self/fd/63' builtin of the script?).  I maintain that there is no
bug except in your script.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9 AT byu DOT net
volunteer cygwin bash maintainer
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