Message-ID: <4BA119E0.60504@redhat.com>
Date: Wed, 17 Mar 2010 12:05:20 -0600
From: Eric Blake <eblake@redhat.com>
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To: cygwin@cygwin.com
Subject: Re: allow executing a path in backslash notation
References: <435451.56628.qm@web88306.mail.re4.yahoo.com> <20100316150700.GZ6505@calimero.vinschen.de>
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On 03/16/2010 09:07 AM, Corinna Vinschen wrote:
> I checked this situation in cmd.exe, and it is not capable of using
> paths relativ to %Path%.  In other words, if %Path% contains a path
> c:\foo and you have two files C:\foo\baz.exe and C:\foo\bar\baz.exe,
> then calling "baz" works, but calling "bar\baz" fails.  OTOH, the
> SearchPath function does it right.

POSIX says PATH searches are only performed on single components; they
are skipped if the argument contains /.  That is:

PATH=3D/b c/d

will NOT execute /b/c/d (unless you happen to be in /b at the time);
rather it MUST execute ./c/d or fail altogether.  Another term for this
(at least, in the bash sources) is the notion of an anchored search -
even though the requested name is relative, the fact that it contains a
/ means it does not trigger a PATH search, but is anchored in the
current directory.

Therefore, I see no reason why we shouldn't behave the same for \, since
we are treating it as a directory separator.  That is, if you have both
c:\foo\baz.exe and c:\foo\bar\baz.exe, then calling bar\baz should NOT
care whether c:\foo is in %Path%, but should only work if .\bar\baz exists.

--=20
Eric Blake   eblake@redhat.com    +1-801-349-2682
Libvirt virtualization library http://libvirt.org


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