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Date:   Wed, 19 Jul 2023 23:16:39 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Sergei Shtepa <sergei.shtepa@veeam.com>
Cc:     Thomas =?iso-8859-1?Q?Wei=DFschuh?= <thomas@t-8ch.de>,
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        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, Donald Buczek <buczek@molgen.mpg.de>
Subject: Re: [PATCH v5 04/11] blksnap: header file of the module interface
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On Tue, Jul 18, 2023 at 11:53:54AM +0200, Sergei Shtepa wrote:
> > Seems a bit weird to have a signed error code that is always negative.
> > Couldn't this be an unsigned number or directly return the error from
> > the ioctl() itself?
> 
> Yes, it's a good idea to pass the error code as an unsigned value.
> And this positive value can be passed in case of successful execution
> of ioctl(), but I would not like to put different error signs in one value.

Linux tends to use negative error values in basically all interfaces.
I think it will be less confusing to stick to that.