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.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
.. c:namespace:: MC
.. _media_request_ioc_reinit:
******************************
ioctl MEDIA_REQUEST_IOC_REINIT
******************************
Name
====
MEDIA_REQUEST_IOC_REINIT - Re-initialize a request
Synopsis
========
.. c:macro:: MEDIA_REQUEST_IOC_REINIT
``int ioctl(int request_fd, MEDIA_REQUEST_IOC_REINIT)``
Arguments
=========
``request_fd``
File descriptor returned by :ref:`MEDIA_IOC_REQUEST_ALLOC`.
Description
===========
If the media device supports :ref:`requests <media-request-api>`, 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 :c:func:`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.
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.
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