xref: /haiku/docs/develop/media/Notifications.txt (revision e81a954787e50e56a7f06f72705b7859b6ab06d1) 
1Messages that can be gathered with BMediaRoster::StartWatching()
2
3for each registered handler, the first message always informs about all exiting nodes, like this:
4
5B_MEDIA_NODE_CREATED:
6BMessage: what = TRIA (0x54524941, or 1414678849)
7    entry  media_node_id, type='LONG', c=7, size= 4, data[0]: 0x1 (1, '')
8                                                     data[1]: 0x2 (2, '')
9                                                     data[2]: 0x3 (3, '')
10                                                     data[3]: 0x4 (4, '')
11                                                     data[4]: 0x5 (5, '')
12                                                     data[5]: 0x7 (7, '')
13                                                     data[6]: 0x8 (8, '')
14
15Creating, connection, disconnecting and deleting looks like this:
16
17B_MEDIA_NODE_CREATED:
18BMessage: what = TRIA (0x54524941, or 1414678849)
19    entry  media_node_id, type='LONG', c=1, size= 4, data[0]: 0x12 (18, '')
20
21B_MEDIA_CONNECTION_MADE:
22BMessage: what = TRIC (0x54524943, or 1414678851)
23    entry         output, type='RAWT', c=1, size=328,
24    entry          input, type='RAWT', c=1, size=328,
25    entry         format, type='RAWT', c=1, size=192,
26    entry    be:old_what, type='LONG', c=1, size= 4, data[0]: 0x54524943 (1414678851, 'TRIC')
27
28B_MEDIA_CONNECTION_BROKEN:
29BMessage: what = TRID (0x54524944, or 1414678852)
30    entry         source, type='RAWT', c=1, size=16,
31    entry    destination, type='RAWT', c=1, size=16,
32    entry    be:old_what, type='LONG', c=1, size= 4, data[0]: 0x54524944 (1414678852, 'TRID')
33
34B_MEDIA_NODE_DELETED:
35BMessage: what = TRIB (0x54524942, or 1414678850)
36    entry  media_node_id, type='LONG', c=1, size= 4, data[0]: 0x12 (18, '')
37
38The following notification is only received if you use the node specific StartWatching,
39and only if the node you are watching uses BroadcastParameterChange()
40
41B_MEDIA_NEW_PARAMETER_VALUE:
42BMessage: what = TRIL (0x5452494c, or 1414678860)
43    entry        be:node, type='RAWT', c=2, size=24,
44    entry   be:parameter, type='LONG', c=1, size= 4, data[0]: 0x2 (2, '')
45    entry        be:when, type='LLNG', c=1, size= 8, data[0]: 0x2388ad126 (9538556198, '')
46    entry       be:value, type='RAWT', c=1, size= 4,
47    entry    be:old_what, type='LONG', c=1, size= 4, data[0]: 0x5452494c (1414678860, 'TRIL')
48
49Other notifications have not been observed so far.