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From: Phil Blundell <pb@pbcl.net>
To: Mark Hatle <mark.hatle@windriver.com>
Date: Fri, 03 May 2013 15:25:01 +0100
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Subject: Re: [PATCH] package.bbclass: Remove redundant chmod/chown operations
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On Thu, 2013-05-02 at 08:41 -0500, Mark Hatle wrote:
> On 5/2/13 8:20 AM, Phil Blundell wrote:
> > These were introduced in 6021e309e69d823e1467648aee12a32182945569.  The
> > code currently reads:
> >
> >                  os.link(file, fpath)
> >                  fstat =3D cpath.stat(file)
> >                  os.chmod(fpath, fstat.st_mode)
> >                  os.chown(fpath, fstat.st_uid, fstat.st_gid)
> >
> > which can have no useful effect since, if "fpath" is a hard link to
> > "file", it will (by definition) have the same mode, uid and gid.
>=20
> I thought there were filesystems where a link operation can result in dif=
ferent=20
> file permissions, owners and groups.  It's rare, but umask and effective =
uid/gid=20
> could play a part in this.=20

I can't think of any POSIX-conformant systems where this would be true.
1003.1 =C2=A73 is fairly clear that file permissions are a property of the
file, not of the link(s) to it, which would prohibit different links
from having different modes or owners.

Can you give a concrete example of such a scenario?

p.