diff options
Diffstat (limited to 'Documentation/userspace-api/media/mediactl/request-func-poll.rst')
| -rw-r--r-- | Documentation/userspace-api/media/mediactl/request-func-poll.rst | 38 |
1 files changed, 5 insertions, 33 deletions
diff --git a/Documentation/userspace-api/media/mediactl/request-func-poll.rst b/Documentation/userspace-api/media/mediactl/request-func-poll.rst index 85a3427e5913..ce0043dbe7da 100644 --- a/Documentation/userspace-api/media/mediactl/request-func-poll.rst +++ b/Documentation/userspace-api/media/mediactl/request-func-poll.rst @@ -1,28 +1,5 @@ -.. This file is dual-licensed: you can use it either under the terms -.. of the GPL 2.0 or the GFDL 1.1+ license, at your option. Note that this -.. dual licensing only applies to this file, and not this project as a -.. whole. -.. -.. a) This file is free software; you can redistribute it and/or -.. modify it under the terms of the GNU General Public License as -.. published by the Free Software Foundation version 2 of -.. the License. -.. -.. This file is distributed in the hope that it will be useful, -.. but WITHOUT ANY WARRANTY; without even the implied warranty of -.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -.. GNU General Public License for more details. -.. -.. Or, alternatively, -.. -.. b) Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/userspace-api/media/fdl-appendix.rst. -.. -.. TODO: replace it to GPL-2.0 OR GFDL-1.1-or-later WITH no-invariant-sections +.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later +.. c:namespace:: MC .. _request-func-poll: @@ -35,7 +12,6 @@ Name request-poll - Wait for some event on a file descriptor - Synopsis ======== @@ -43,9 +19,7 @@ Synopsis #include <sys/poll.h> - .. c:function:: int poll( struct pollfd *ufds, unsigned int nfds, int timeout ) - :name: request-poll Arguments ========= @@ -59,14 +33,13 @@ Arguments ``timeout`` Timeout to wait for events - Description =========== -With the :c:func:`poll() <request-func-poll>` function applications can wait +With the :c:func:`poll()` function applications can wait for a request to complete. -On success :c:func:`poll() <request-func-poll>` returns the number of file +On success :c:func:`poll()` returns the number of file descriptors that have been selected (that is, file descriptors for which the ``revents`` field of the respective struct :c:type:`pollfd` is non-zero). Request file descriptor set the ``POLLPRI`` flag in ``revents`` @@ -77,11 +50,10 @@ set appropriately. Attempting to poll for a request that is not yet queued will set the ``POLLERR`` flag in ``revents``. - Return Value ============ -On success, :c:func:`poll() <request-func-poll>` returns the number of +On success, :c:func:`poll()` returns the number of structures which have non-zero ``revents`` fields, or zero if the call timed out. On error -1 is returned, and the ``errno`` variable is set appropriately: |