alZeroFrames(3dm) alZeroFrames(3dm) NAME alZeroFrames - write zero-valued sample frames to an audio port SYNOPSIS #include <dmedia/audio.h> int alZeroFrames(const ALport port, const int framecount) PARAMETER port is the audio output port to which you want to write samples. This is the returned value of an alOpenPort(3dm) call. framecount is the number of sample frames that you want to write to the audio port. DESCRIPTION alZeroFrames writes a given number of zero-valued sample frames to the specified audio port. alZeroFrames blocks until framecount sample frames have been written to the port. If you do not wish to block, make sure that framecount is less than the return value of alGetFillable(3dm). alZeroFrames is a convenience function, equivalent to calling alWriteFrames(3dm) with a zero-valued buffer of the given size. However, alZeroFrames is simpler, particularly when framecount is large; it avoids having to allocate a large buffer or iterate over many writes of a smaller buffer. It is also more efficient than the equivalent alWriteFrames call. Note that since an audio port contains an internal queue, zero-valued frames written to the port will not immediately come out the associated audio device or devices. alGetFilled(3dm) will indicate how many samples are currently in this queue. Also, alGetFrameTime(3dm) and alGetFrameNumber(3dm) provide facilities for precise synchronization of audio and other media. In order to achieve the best possible performance, alZeroFrames does not attempt to verify that port or samples are valid. You should make certain these values are valid before passing them as arguments to alZeroFrames. DIAGNOSTICS alZeroFrames always returns 0. SEE ALSO alOpenPort(3dm), alGetFillable(3dm), alGetFilled(3dm), alSetChannels(3dm), alSetWidth(3dm), alReadFrames(3dm), alSetSampFmt(3dm), alSetFloatMax(3dm) Page 1