Documentation/linux_tv/media/dvb/ca-fopen.rst

   1 .. -*- coding: utf-8; mode: rst -*-
   2
   3 .. _ca_fopen:
   4
   5 =============
   6 DVB CA open()
   7 =============
   8
   9 NAME
  10 ----
  11
  12 DVB CA open()
  13
  14 SYNOPSIS
  15 --------
  16
  17 .. cpp:function:: int  open(const char *deviceName, int flags)
  18
  19
  20 ARGUMENTS
  21 ---------
  22
  23 .. flat-table::
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  26
  27
  28     -  .. row 1
  29
  30        -  const char \*deviceName
  31
  32        -  Name of specific video device.
  33
  34     -  .. row 2
  35
  36        -  int flags
  37
  38        -  A bit-wise OR of the following flags:
  39
  40     -  .. row 3
  41
  42        -
  43        -  O_RDONLY read-only access
  44
  45     -  .. row 4
  46
  47        -
  48        -  O_RDWR read/write access
  49
  50     -  .. row 5
  51
  52        -
  53        -  O_NONBLOCK open in non-blocking mode
  54
  55     -  .. row 6
  56
  57        -
  58        -  (blocking mode is the default)
  59
  60
  61 DESCRIPTION
  62 -----------
  63
  64 This system call opens a named ca device (e.g. /dev/ost/ca) for
  65 subsequent use.
  66
  67 When an open() call has succeeded, the device will be ready for use. The
  68 significance of blocking or non-blocking mode is described in the
  69 documentation for functions where there is a difference. It does not
  70 affect the semantics of the open() call itself. A device opened in
  71 blocking mode can later be put into non-blocking mode (and vice versa)
  72 using the F_SETFL command of the fcntl system call. This is a standard
  73 system call, documented in the Linux manual page for fcntl. Only one
  74 user can open the CA Device in O_RDWR mode. All other attempts to open
  75 the device in this mode will fail, and an error code will be returned.
  76
  77
  78 RETURN VALUE
  79 ------------
  80
  81 .. flat-table::
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  85
  86     -  .. row 1
  87
  88        -  ``ENODEV``
  89
  90        -  Device driver not loaded/available.
  91
  92     -  .. row 2
  93
  94        -  ``EINTERNAL``
  95
  96        -  Internal error.
  97
  98     -  .. row 3
  99
 100        -  ``EBUSY``
 101
 102        -  Device or resource busy.
 103
 104     -  .. row 4
 105
 106        -  ``EINVAL``
 107
 108        -  Invalid argument.