> On Thu, 2009-06-04 at 11:18 +0200, Laurent Pinchart wrote:
>> Hi,
>>
>> On Thursday 04 June 2009 06:20:07 figo.zhang wrote:
>> > The function video_register_device() will call the
>> > video_register_device_index(). In this function, firtly it will do
>> some
>> > argments check , if failed,it will return a negative number such as
>> > -EINVAL, and then do cdev_alloc() and device_register(), if success
>> return
>> > zero. so video_register_device_index() canot return a a positive
>> number.
>> >
>> > for example, see the drivers/media/video/stk-webcam.c (line 1325):
>> >
>> > err = video_register_device(&dev->vdev, VFL_TYPE_GRABBER, -1);
>> > if (err)
>> > STK_ERROR("v4l registration failed\n");
>> > else
>> > STK_INFO("Syntek USB2.0 Camera is now controlling video device"
>> > " /dev/video%d\n", dev->vdev.num);
>> >
>> > in my opinion, it will be cleaner to do something like this:
>> >
>> > err = video_register_device(&dev->vdev, VFL_TYPE_GRABBER, -1);
>> > if (err != 0)
>> > STK_ERROR("v4l registration failed\n");
>> > else
>> > STK_INFO("Syntek USB2.0 Camera is now controlling video device"
>> > " /dev/video%d\n", dev->vdev.num);
>>
>> What's the difference ? (err != 0) and (err) are identical.
>>
>> Best regards,
>>
>> Laurent Pinchart
>
> yes, it is the same, but it is easy for reading.
To be honest, I think '(err)' is easier to read. Unless there is some new
CodingStyle rule I'm not aware of I see no reason for applying these
changes.
Regards,
Hans
--
Hans Verkuil - video4linux developer - sponsored by TANDBERG
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
