[alsa-devel] Which project to choose?

David Henningsson launchpad.web at epost.diwic.se
Wed Jul 14 21:45:21 CEST 2010

2010-07-14 17:25, Jaroslav Kysela skrev:
> On Wed, 14 Jul 2010, David Henningsson wrote:
>> 2010-07-14 13:13, Raymond Yau skrev:
>>> localhost pulseaudio[24553]: alsa-util.c:   appl_ptr     : 735801008
>>> localhost pulseaudio[24553]: alsa-util.c:   hw_ptr       : 735846184
>>> This is underrun as you can see appl_ptr is behing hw_ptr
>> Ehm, isn't that a ring buffer? I e, there is nothing wrong with appl_ptr
>> being less than hw_ptr.
> For playback, if appl_ptr is less than hw_ptr, it's underrun situation
> (application didn't feed samples in time to the driver's ring buffer).
> Note that pointers in ALSA are in range 0..boundary not
> 0..ring_buffer_size (boundary is near LONG_MAX value) - it's design to
> detect such situations (underrun, overrun).

Okay, thanks for the clarification. But LONG_MAX (as in 2^31) would
still wrap around every thirteen hours (at 44100 Hz), so are we having
bugs, such as e g failure to detect underruns, at those occasions?

// David

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