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ioctl MEDIA_REQUEST_IOC_REINIT

Documentation/userspace-api/media/mediactl/media-request-ioc-reinit.rst

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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.