summaryrefslogblamecommitdiffstats
path: root/Documentation/media/uapi/dvb/dmx-fopen.rst
blob: a697e33c32ea50726e158e66bb5c5631e592c06a (plain) (tree)
1
2
3
4
5
6
7
8
9



                                   
                


                
    
    
 
                
 

        

        
                                                           
                       
 
         
         
 





                                       



                    


                         
 


                          
 



                                       

 
           
           
 















                                                                        

 
            

            



























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

.. _dmx_fopen:

================
DVB demux open()
================

Name
----

DVB demux open()


Synopsis
--------

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

Arguments
---------

``name``
  Name of specific DVB demux 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, used with a device name of /dev/dvb/adapter0/demux0,
allocates a new filter and returns a handle which can be used for
subsequent control of that filter. This call has to be made for each
filter to be used, i.e. every returned file descriptor is a reference to
a single filter. /dev/dvb/adapter0/dvr0 is a logical device to be used
for retrieving Transport Streams for digital video recording. When
reading from this device a transport stream containing the packets from
all PES filters set in the corresponding demux device
(/dev/dvb/adapter0/demux0) having the output set to DMX_OUT_TS_TAP. A
recorded Transport Stream is replayed by writing to this device.

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.


Return Value
------------

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


    -  .. row 1

       -  ``ENODEV``

       -  Device driver not loaded/available.

    -  .. row 2

       -  ``EINVAL``

       -  Invalid argument.

    -  .. row 3

       -  ``EMFILE``

       -  “Too many open files”, i.e. no more filters available.

    -  .. row 4

       -  ``ENOMEM``

       -  The driver failed to allocate enough memory.