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Linux kernel mirror (for testing)
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1.. -*- coding: utf-8; mode: rst -*-
2
3.. _FE_READ_STATUS:
4
5********************
6ioctl FE_READ_STATUS
7********************
8
9Name
10====
11
12FE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device
13
14
15Synopsis
16========
17
18.. c:function:: int ioctl( int fd, FE_READ_STATUS, unsigned int *status )
19 :name: FE_READ_STATUS
20
21
22Arguments
23=========
24
25``fd``
26 File descriptor returned by :ref:`open() <frontend_f_open>`.
27
28``status``
29 pointer to a bitmask integer filled with the values defined by enum
30 :c:type:`fe_status`.
31
32
33Description
34===========
35
36All DVB frontend devices support the ``FE_READ_STATUS`` ioctl. It is
37used to check about the locking status of the frontend after being
38tuned. The ioctl takes a pointer to an integer where the status will be
39written.
40
41.. note::
42
43 The size of status is actually sizeof(enum fe_status), with
44 varies according with the architecture. This needs to be fixed in the
45 future.
46
47
48int fe_status
49=============
50
51The fe_status parameter is used to indicate the current state and/or
52state changes of the frontend hardware. It is produced using the enum
53:c:type:`fe_status` values on a bitmask
54
55.. c:type:: fe_status
56
57.. tabularcolumns:: |p{3.5cm}|p{14.0cm}|
58
59.. _fe-status:
60
61.. flat-table:: enum fe_status
62 :header-rows: 1
63 :stub-columns: 0
64
65
66 - .. row 1
67
68 - ID
69
70 - Description
71
72 - .. row 2
73
74 - .. _FE-HAS-SIGNAL:
75
76 ``FE_HAS_SIGNAL``
77
78 - The frontend has found something above the noise level
79
80 - .. row 3
81
82 - .. _FE-HAS-CARRIER:
83
84 ``FE_HAS_CARRIER``
85
86 - The frontend has found a DVB signal
87
88 - .. row 4
89
90 - .. _FE-HAS-VITERBI:
91
92 ``FE_HAS_VITERBI``
93
94 - The frontend FEC inner coding (Viterbi, LDPC or other inner code)
95 is stable
96
97 - .. row 5
98
99 - .. _FE-HAS-SYNC:
100
101 ``FE_HAS_SYNC``
102
103 - Synchronization bytes was found
104
105 - .. row 6
106
107 - .. _FE-HAS-LOCK:
108
109 ``FE_HAS_LOCK``
110
111 - The DVB were locked and everything is working
112
113 - .. row 7
114
115 - .. _FE-TIMEDOUT:
116
117 ``FE_TIMEDOUT``
118
119 - no lock within the last about 2 seconds
120
121 - .. row 8
122
123 - .. _FE-REINIT:
124
125 ``FE_REINIT``
126
127 - The frontend was reinitialized, application is recommended to
128 reset DiSEqC, tone and parameters
129
130
131Return Value
132============
133
134On success 0 is returned, on error -1 and the ``errno`` variable is set
135appropriately. The generic error codes are described at the
136:ref:`Generic Error Codes <gen-errors>` chapter.