Updates the playback buffer of a stream or MOD music.
BOOL BASS_ChannelUpdate( DWORD handle, DWORD length );
|handle||The channel handle... a HMUSIC or HSTREAM.|
|length||The amount of data to render, in milliseconds... 0 = default (2 x update period). This is capped at the space available in the buffer.|
|BASS_ERROR_HANDLE||handle is not a valid channel.|
|BASS_ERROR_NOTAVAIL||Decoding channels do not have playback buffers.|
|BASS_ERROR_ENDED||The channel has ended.|
|BASS_ERROR_ALREADY||The channel is already being updated.|
|BASS_ERROR_UNKNOWN||Some other mystery problem!|
It may not always be possible to render the requested amount of data, in which case this function will still succeed. BASS_ChannelGetData (BASS_DATA_AVAILABLE) can be used to check how much data a channel has buffered for playback.
When automatic updating is disabled (BASS_CONFIG_UPDATEPERIOD = 0 or BASS_CONFIG_UPDATETHREADS = 0), this function could be used instead of BASS_Update to implement different update periods for different channels, instead of a single update period for all. Unlike BASS_Update, this function can also be used while automatic updating is enabled.
The CPU usage of this function is not included in the BASS_GetCPU reading, but is included in the channel's BASS_ATTRIB_CPU attribute value.