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
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
