OpenCloudOS-Kernel/Documentation/media/uapi/dvb/ca-fopen.rst

112 lines
1.9 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _ca_fopen:
=============
DVB CA open()
=============
Name
----
DVB CA open()
Synopsis
--------
.. c:function:: int open(const char *deviceName, int flags)
Arguments
---------
.. flat-table::
:header-rows: 0
:stub-columns: 0
- .. row 1
- const char \*deviceName
- Name of specific video device.
- .. row 2
- int flags
- A bit-wise OR of the following flags:
- .. row 3
-
- O_RDONLY read-only access
- .. row 4
-
- O_RDWR read/write access
- .. row 5
-
- O_NONBLOCK open in non-blocking mode
- .. row 6
-
- (blocking mode is the default)
Description
-----------
This system call opens a named ca device (e.g. /dev/ost/ca) for
subsequent use.
When an open() call has succeeded, the device will be ready for use. The
significance of blocking or non-blocking mode is described in the
documentation for functions where there is a difference. It does not
affect the semantics of the open() call itself. A device opened in
blocking mode can later be put into non-blocking mode (and vice versa)
using the F_SETFL command of the fcntl system call. This is a standard
system call, documented in the Linux manual page for fcntl. Only one
user can open the CA Device in O_RDWR mode. All other attempts to open
the device in this mode will fail, and an error code will be returned.
Return Value
------------
.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|
.. flat-table::
:header-rows: 0
:stub-columns: 0
- .. row 1
- ``ENODEV``
- Device driver not loaded/available.
- .. row 2
- ``EINTERNAL``
- Internal error.
- .. row 3
- ``EBUSY``
- Device or resource busy.
- .. row 4
- ``EINVAL``
- Invalid argument.