xref: /linux/Documentation/userspace-api/media/dvb/ca-get-msg.rst (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2.. c:namespace:: DTV.ca
3
4.. _CA_GET_MSG:
5
6==========
7CA_GET_MSG
8==========
9
10Name
11----
12
13CA_GET_MSG
14
15Synopsis
16--------
17
18.. c:macro:: CA_GET_MSG
19
20``int ioctl(fd, CA_GET_MSG, struct ca_msg *msg)``
21
22Arguments
23---------
24
25``fd``
26  File descriptor returned by a previous call to :c:func:`open()`.
27
28``msg``
29  Pointer to struct :c:type:`ca_msg`.
30
31Description
32-----------
33
34Receives a message via a CI CA module.
35
36.. note::
37
38   Please notice that, on most drivers, this is done by reading from
39   the /dev/adapter?/ca? device node.
40
41Return Value
42------------
43
44On success 0 is returned.
45
46On error -1 is returned, and the ``errno`` variable is set
47appropriately.
48
49Generic error codes are described at the
50:ref:`Generic Error Codes <gen-errors>` chapter.
51