1.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
2.. c:namespace:: MC
3
4.. _media_request_ioc_reinit:
5
6******************************
7ioctl MEDIA_REQUEST_IOC_REINIT
8******************************
9
10Name
11====
12
13MEDIA_REQUEST_IOC_REINIT - Re-initialize a request
14
15Synopsis
16========
17
18.. c:macro:: MEDIA_REQUEST_IOC_REINIT
19
20``int ioctl(int request_fd, MEDIA_REQUEST_IOC_REINIT)``
21
22Arguments
23=========
24
25``request_fd``
26    File descriptor returned by :ref:`MEDIA_IOC_REQUEST_ALLOC`.
27
28Description
29===========
30
31If the media device supports :ref:`requests <media-request-api>`, then
32this request ioctl can be used to re-initialize a previously allocated
33request.
34
35Re-initializing a request will clear any existing data from the request.
36This avoids having to :c:func:`close()` a completed
37request and allocate a new request. Instead the completed request can just
38be re-initialized and it is ready to be used again.
39
40A request can only be re-initialized if it either has not been queued
41yet, or if it was queued and completed. Otherwise it will set ``errno``
42to ``EBUSY``. No other error codes can be returned.
43
44Return Value
45============
46
47On success 0 is returned, on error -1 and the ``errno`` variable is set
48appropriately.
49
50EBUSY
51    The request is queued but not yet completed.
52