From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH 2/2] git: continue alias lookup on EACCES errors
Date: Wed, 28 Mar 2012 13:04:04 -0500
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Cc: Junio C Hamano <gitster@pobox.com>,
	James Pickens <jepicken@gmail.com>,
	Git ML <git@vger.kernel.org>
To: Jeff King <peff@peff.net>
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Jeff King wrote:
> On Wed, Mar 28, 2012 at 10:42:26AM -0700, Junio C Hamano wrote:

>> I am leaning to think that it would be the least surprising if we treat as
>> if /bin/ls does not even exist if /bin is not searchable.  If /bin/ls is
>> unreadable or unexecutable but /bin is searchable, then we _know_ it
>> exists, and we follow the usual exec*p() rule to ignore it
[...]
> That sounds sensible to me. I think it involves writing our own
> execvp, though, right?

If I understood Junio correctly, then checking for ENOENT and EACCES
should be enough.

Example: when I try

 :; mkdir $HOME/cannotread
 :; chmod -x $HOME/cannotread
 :; echo nonsense >$HOME/bin/cat
 :; chmod -x $HOME/bin/cat
 :; PATH=$HOME/cannotread:$HOME/bin/cat:/usr/local/bin:/usr/bin:/bin
 :; cat /etc/fstab

the shell uses /bin/cat without complaint.