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1.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later2.. c:namespace:: MC3 4.. _media_request_ioc_reinit:5 6******************************7ioctl MEDIA_REQUEST_IOC_REINIT8******************************9 10Name11====12 13MEDIA_REQUEST_IOC_REINIT - Re-initialize a request14 15Synopsis16========17 18.. c:macro:: MEDIA_REQUEST_IOC_REINIT19 20``int ioctl(int request_fd, MEDIA_REQUEST_IOC_REINIT)``21 22Arguments23=========24 25``request_fd``26 File descriptor returned by :ref:`MEDIA_IOC_REQUEST_ALLOC`.27 28Description29===========30 31If the media device supports :ref:`requests <media-request-api>`, then32this request ioctl can be used to re-initialize a previously allocated33request.34 35Re-initializing a request will clear any existing data from the request.36This avoids having to :c:func:`close()` a completed37request and allocate a new request. Instead the completed request can just38be re-initialized and it is ready to be used again.39 40A request can only be re-initialized if it either has not been queued41yet, or if it was queued and completed. Otherwise it will set ``errno``42to ``EBUSY``. No other error codes can be returned.43 44Return Value45============46 47On success 0 is returned, on error -1 and the ``errno`` variable is set48appropriately.49 50EBUSY51 The request is queued but not yet completed.52