From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Subject: Re: bash: Correct usage of F_SETFD
Date: Tue, 23 Nov 2010 09:51:57 -0800
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Cc: linux-fsdevel@vger.kernel.org, chet.ramey@case.edu, bug-bash@gnu.org,
	chet@po.cwru.edu, Matthew Wilcox <matthew@wil.cx>
To: Eric Blake <eblake@redhat.com>
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Eric Blake [eblake@redhat.com] wrote:
| > 
| > So if bash is the one creating its file descriptors, there's no need to
| > use R/M/W since it knows what the state of them are.
| 
| No, bash cannot reasonably know what the implementation's default bit
| state is, and blindly setting all other bits to zero is very possibly a
| bug, and easy enough to avoid by using the full R/M/W.

Besides, if user sets a flag on the fd and execs bash, bash would clobber
the flag. IOW, assuming that bash is the one creating the fd is not always
safe right ?

Thanks,

Sukadev