Re: [Qemu-devel] [PATCH] linux-user: add binfmt wrapper for argv[0] handling

[Alexander Graf]

On 31.10.2011, at 12:16, Riku Voipio <address@hidden> wrote:

> On Sat, Oct 29, 2011 at 08:08:39PM +0200, Alexander Graf wrote:
>>> When using qemu's linux-user binaries through binfmt, argv[0] gets lost
>>> along the execution because qemu only gets passed in the full file name
>>> to the executable while argv[0] can be something completely different.
>>> 
>>> This breaks in some subtile situations, such as the grep and make test
>>> suites.
>>> 
>>> This patch adds a wrapper binary called qemu-$TARGET-binfmt that can be
>>> used with binfmt's P flag which passes the full path _and_ argv[0] to
>>> the binfmt handler.
>>> 
>>> The binary would be smart enough to be versatile and only exist in the
>>> system once, creating the qemu binary path names from its own argv[0].
>>> However, this seemed like it didn't fit the make system too well, so
>>> we're currently creating a new binary for each target archictecture.
>>> 
>>> CC: Reinhard Max <address@hidden>
>>> Signed-off-by: Alexander Graf <address@hidden>
> 
>> Ping?
> 
> Last time a wrapper for binfmt was suggested on this list, it was shot down
> since people didn't want to add extra binary to the chroot. But your point
> is valid, without proper argv[0] things break sometimes. For the same reason
> scratchbox has a wrapper binary instead of calling qemu directly...

Yup. And I really don't want to have downstreams diverge because we're not 
pragmatic enough :).

Alex

>