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.. -*- coding: utf-8; mode: rst -*-

.. _ca_fopen:

=============
DVB CA open()
=============

Name
----

DVB CA open()


Synopsis
--------

.. c:function:: int open(const char *name, int flags)
    :name: dvb-ca-open


Arguments
---------

``name``
  Name of specific DVB CA device.

``flags``
  A bit-wise OR of the following flags:

.. flat-table::
    :header-rows:  0
    :stub-columns: 0

    -
       - O_RDONLY
       - read-only access

    -
       - O_RDWR
       - read/write access

    -
       - O_NONBLOCK
       - open in non-blocking mode
         (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
------------


On success 0 is returned.

On error -1 is returned, and the ``errno`` variable is set
appropriately.

Generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.