| 1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | |
| 3 | .. _audio_fopen: |
| 4 | |
| 5 | ================ |
| 6 | DVB audio open() |
| 7 | ================ |
| 8 | |
| 9 | Name |
| 10 | ---- |
| 11 | |
| 12 | DVB audio open() |
| 13 | |
| 14 | |
| 15 | Synopsis |
| 16 | -------- |
| 17 | |
| 18 | .. c:function:: int open(const char *deviceName, int flags) |
| 19 | |
| 20 | |
| 21 | Arguments |
| 22 | --------- |
| 23 | |
| 24 | .. flat-table:: |
| 25 | :header-rows: 0 |
| 26 | :stub-columns: 0 |
| 27 | |
| 28 | |
| 29 | - .. row 1 |
| 30 | |
| 31 | - const char \*deviceName |
| 32 | |
| 33 | - Name of specific audio 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 audio device (e.g. |
| 66 | /dev/dvb/adapter0/audio0) for subsequent use. When an open() call has |
| 67 | succeeded, the device will be ready for use. The significance of |
| 68 | blocking or non-blocking mode is described in the documentation for |
| 69 | functions where there is a difference. It does not affect the semantics |
| 70 | of the open() call itself. A device opened in blocking mode can later be |
| 71 | put into non-blocking mode (and vice versa) using the F_SETFL command |
| 72 | of the fcntl system call. This is a standard system call, documented in |
| 73 | the Linux manual page for fcntl. Only one user can open the Audio Device |
| 74 | in O_RDWR mode. All other attempts to open the device in this mode will |
| 75 | fail, and an error code will be returned. If the Audio Device is opened |
| 76 | in O_RDONLY mode, the only ioctl call that can be used is |
| 77 | AUDIO_GET_STATUS. All other call will return with an error code. |
| 78 | |
| 79 | |
| 80 | Return Value |
| 81 | ------------ |
| 82 | |
| 83 | .. tabularcolumns:: |p{2.5cm}|p{15.0cm}| |
| 84 | |
| 85 | .. flat-table:: |
| 86 | :header-rows: 0 |
| 87 | :stub-columns: 0 |
| 88 | |
| 89 | |
| 90 | - .. row 1 |
| 91 | |
| 92 | - ``ENODEV`` |
| 93 | |
| 94 | - Device driver not loaded/available. |
| 95 | |
| 96 | - .. row 2 |
| 97 | |
| 98 | - ``EBUSY`` |
| 99 | |
| 100 | - Device or resource busy. |
| 101 | |
| 102 | - .. row 3 |
| 103 | |
| 104 | - ``EINVAL`` |
| 105 | |
| 106 | - Invalid argument. |