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