Jan Deinhard wrote:
I would like to understand the following quote which I copied from https://www.kernel.org/doc/Documentation/sound/alsa/timestamping.txt
"The ALSA API provides two basic pieces of information, avail and delay, which combined with the trigger and current system timestamps allow for applications to keep track of the 'fullness' of the ring buffer and the amount of queued samples."
The trigger/current timestamps are not related to the buffer/queue. They are useful only to relate the audio stream position to the system time.
What exactly is meant by "current system timestamp"? Is it provied by ALSA (htstamp?) or should I use clock_gettime(CLOCK_MONOTONIC, &system_time); to get that timestamp?
They are the same. ALSA returns it to prevent your process from being interrupted between measuring the two clocks.
Regards, Clemens