6.14. ioctl MEDIA_REQUEST_IOC_REINIT¶
6.14.1. Name¶
MEDIA_REQUEST_IOC_REINIT - Re-initialize a request
6.14.2. Synopsis¶
-
int
ioctl
(int request_fd, MEDIA_REQUEST_IOC_REINIT)¶
6.14.3. Arguments¶
request_fd
- File descriptor returned by ioctl MEDIA_IOC_REQUEST_ALLOC.
6.14.4. Description¶
If the media device supports requests, then this request ioctl can be used to re-initialize a previously allocated request.
Re-initializing a request will clear any existing data from the request. This avoids having to close() a completed request and allocate a new request. Instead the completed request can just be re-initialized and it is ready to be used again.
A request can only be re-initialized if it either has not been queued
yet, or if it was queued and completed. Otherwise it will set errno
to EBUSY
. No other error codes can be returned.
6.14.5. Return Value¶
On success 0 is returned, on error -1 and the errno
variable is set
appropriately.
- EBUSY
- The request is queued but not yet completed.