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Date: Tue, 21 Jun 2011 18:18:57 +0200
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] qemu-char: Print strerror message on
	failure
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To: Markus Armbruster <armbru@redhat.com>
Cc: qemu-devel@nongnu.org

Am 21.06.2011 18:09, schrieb Markus Armbruster:
> Kevin Wolf <kwolf@redhat.com> writes:
> 
>> The only way for chardev drivers to communicate an error was to return a NULL
>> pointer, which resulted in an error message that said _that_ something went
>> wrong, but not _why_.
>>
>> This patch changes the interface to return 0/-errno and updates
>> qemu_chr_open_opts to use strerror to display a more helpful error message.
> 
> Returning the result through a pointer is awkward.  What about stuffing
> the error code into errno?

I generally like it better to return error codes explicitly instead of
storing them in some global variable where it tends to be trampled over
before you print the message. But if people prefer it that way, I can
redo the patch.

Kevin