period time in async handler

period time in async handler

[Tim Pushor]

Hi Friends,

I have a need to have an audio player kick off things at various points 
of time through playback of an audio file. I'm trying to hack aplay as a 
proof of concept.

If I understand correctly, the asynchronous handler seems to do what I 
want. I hacked in a handler to aplay and it works, but not quite like 
how I expected.

I counted the number of times that the handler got called, and thought 
that if I multiplied that by the period time that I'd end up with the 
total audio length but that doesn't seem to be the case. I was under the 
assumption that the handler was called once per period.

I must not understand the relationship of the asynchronous handler and 
period_time. Does this make sense? Am I going about this all wrong?

Thanks,
Tim

Re: period time in async handler

[Takashi Iwai]

At Tue, 10 Jun 2008 20:35:12 -0600,
Tim Pushor wrote:
> 
> Hi Friends,
> 
> I have a need to have an audio player kick off things at various points 
> of time through playback of an audio file. I'm trying to hack aplay as a 
> proof of concept.
> 
> If I understand correctly, the asynchronous handler seems to do what I 
> want. I hacked in a handler to aplay and it works, but not quite like 
> how I expected.

Oh, forget about async handler.  It's a horrible hack, and in
principle, never guaranteed to work.

We really need to put DONT_USE tag to async handler APIs...


Takashi

> I counted the number of times that the handler got called, and thought 
> that if I multiplied that by the period time that I'd end up with the 
> total audio length but that doesn't seem to be the case. I was under the 
> assumption that the handler was called once per period.
> 
> I must not understand the relationship of the asynchronous handler and 
> period_time. Does this make sense? Am I going about this all wrong?
> 
> Thanks,
> Tim
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