bin/153261: sed: fix for a race condition (from illumos)

[Pedro F. Giffuni]

The following reply was made to PR bin/153261; it has been noted by GNATS.

From: "Pedro F. Giffuni" <giffunip at tutopia.com>
To: bug-followup at FreeBSD.org, Jilles Tjoelker <jilles at stack.nl>
Cc:  
Subject: Re: bin/153261: sed: fix for a race condition (from illumos)
Date: Wed, 29 Dec 2010 10:51:23 -0800 (PST)

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 Garret D'Amore (from Illumos) has provided some feedback:
 ____
 Thanks.  Two issues:
 
 a) On Solaris, the errno is ENOSYS, not EOPNOTSUPP. 
 
 b) The "unlink(tmpfname)" and exit(1) logic don't seem to be honored in
 the case of rename() failing.
 
 I think the simpler solution is to unconditionally try the rename() if
 link fails, and not worry about a difference in the error message. 
 
 I also noticed that we unconditionally try to unlink(tmpfname), but that
 only makes sense if tmpfname is a non-empty string. :-)
 ____
 
 So I attach a new patch.
 
 
       
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