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Date: Sun, 09 Feb 2014 07:46:03 +0100
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Subject: Re: [Qemu-devel] [PATCH v19 11/11] module: Pass argv[0] along the
 module load path
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, Michael Tokarev <mjt@tls.msk.ru>, QEMU Developers <qemu-devel@nongnu.org>, Alex Bligh <alex@alex.org.uk>, Miroslav Rezanina <mrezanin@redhat.com>, =?UTF-8?B?TGx1w61zIFZpbGFub3Zh?= <vilanova@ac.upc.edu>, Richard Henderson <rth@twiddle.net>

Il 09/02/2014 01:18, Peter Maydell ha scritto:
> Haven't checked it yet. I just don't really see what the point is
> in having a huge amount of OS specific code to do something
> which we already do in a portable way. It might be nice to abstract
> out stashing initial-argv0 and adding a utility function for it.
>
> If we do want to use OS-specific code, then we should be
> consistent, ie change the datadir lookup to use it.

It is using it already.  argv[0] is just a fallback, and Fam's patches 
moved the OS-specific code of os_find_datadir out of it so that module 
loading could reuse it.

I think there are cases where argv[0] cannot work, such as using the 
exec system call to invoke QEMU, and specifying a different argv[0] than 
the actually executed file; or invoking a non-installed QEMU executable 
by putting its directory in the PATH.  They are probably not happening 
in practice, but they are there.

Paolo