net-get-if.rst

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

.. _NET_GET_IF:

****************
ioctl NET_GET_IF
****************

Name
====

NET_GET_IF - Read the configuration data of an interface created via - :ref:`NET_ADD_IF <net>`.


Synopsis
========

.. cpp:function:: int ioctl( int fd, int request, struct dvb_net_if *net_if )


Arguments
=========

``fd``
    File descriptor returned by :ref:`open() <frontend_f_open>`.

``request``
    FE_SET_TONE

``net_if``
    pointer to struct :ref:`dvb_net_if <dvb-net-if>`


Description
===========

The NET_GET_IF ioctl uses the interface number given by the struct
:ref:`dvb_net_if <dvb-net-if>`::ifnum field and fills the content of
struct :ref:`dvb_net_if <dvb-net-if>` with the packet ID and
encapsulation type used on such interface. If the interface was not
created yet with :ref:`NET_ADD_IF <net>`, it will return -1 and fill
the ``errno`` with ``EINVAL`` error code.


Return Value
============

On success 0 is returned, on error -1 and the ``errno`` variable is set
appropriately. The generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.