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dmGetUST(3dm)

ALgetframenumber(3A)

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ALgetframetime(3dm)                                        ALgetframetime(3dm)



NAME
     ALgetframetime - (obsolete) Get the time at which a sample frame came in
     or will go out

SYNOPSIS
     #include <dmedia/audio.h>

     int ALgetframetime(const ALport port, unsigned long long *fnum, unsigned long long *time)

PARAMETERS
     port expects the ALport structure for the audio port for which you wish
          to know the sample frame number.  This structure is the returned
          value of the ALopenport(3dm) call.

     fnum expects a pointer to an unsigned 64-bit value which is to contain
          the resultant sample-frame number.

     time expects a pointer to an unsigned 64-bit value which is to contain
          the resultant sample-frame time, in nanoseconds.

DESCRIPTION
     ALgetframetime is obsolete and is provided for backward compatibility.
     The preferred function is alGetFrameTime(3dm).

     ALgetframetime returns an atomic pair of (fnum, time). For an input port,
     the time returned is the time at which the returned sample frame arrived
     at the electrical input on the machine. For an output port, the time
     returned is the time at which the returned sample frame will arrive at
     the electrical output on the machine. ALgetframetime therefore accounts
     for all the latency within the machine, including the group delay of the
     A/D and D/A converters.

     The returned sample frame number is not guaranteed to be in any
     application's port. For example, an input sample frame as returned by
     ALgetframetime may be "in the future": it has not yet arrived in any
     application's port. Similarly, an output sample frame may be "in the
     past": it has already gone out of some application's port. In order to
     relate the sample frame numbers to those of a particular application's
     audio port, the ALgetframenumber call must be used.

     ALgetframetime uses the Unadjusted System Time (UST) as its timeline.
     This allows it to relate to other media which also use UST. See the man
     page for dmGetUST(3dm) for more information on UST.

     ALgetframetime can fail for the following reasons:

     ALBADPORT
          port is invalid.

     ALBADNOTIMPLEMENTED
          the feature is not implemented on the given machine. ALgetframetime
          is not implemented on Indigo (IP12), 4D/35 (IP12), and Indigo R4K



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ALgetframetime(3dm)                                        ALgetframetime(3dm)



          (IP20) systems.


DIAGNOSTICS
     Upon successful completion, ALgetframetime(3dm) returns 0. Otherwise
     ALgetframetime(3dm) returns -1 and sets an error number which can be
     retrieved with oserror(3C).

SEE ALSO
     dmGetUST(3dm), ALgetframenumber(3A), oserror(3C)













































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