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GetTimeBaseInfo

void GetTimeBaseInfo (
                     UInt32 *minAbsoluteTimeDelta,
                     UInt32 *theAbsoluteTimeToNanosecondNumerator,
                     UInt32 *theAbsoluteTimeToNanosecondDenominator,
                     UInt32 *theProcessorToAbsoluteTimeNumerator,
                     UInt32 *theProcessorToAbsoluteTimeDenominator);
<-- minAbsoluteTimeDelta
Minimum number of AbsoluteTime units between time changes.
<-- theAbsoluteTimeToNanosecondNumerator
Absolute to nanoseconds numerator.
<-- theAbsoluteTimeToNanosecondDenominator
Absolute to nanoseconds denominator.
<-- theProcessorToAbsoluteTimeNumerator
Processor time to absolute numerator.
<-- theProcessorToAbsoluteTimeDenominator
Processor time to absolute denominator.
DESCRIPTION

The GetTimeBase function returns information used to determine the current hardware time base in fractional form--two 32-bit integer values, a numerator and denominator. The minAbsoluteTimeDelta value is the minimum number of AbsoluteTime units that can change at any given time. If you multiply an AbsoluteTime value by the value of theAbsoluteTimeToNanosecondNumerator and divide the result by the value of theAbsoluteTimeToNanosecondDenominator, the result is nanoseconds.For example, if the Power Macintosh hardware changes the decrementer in quantities of 128, then the minAbsoluteTimeDelta value returned by GetTimeBaseInfo would be 128.

EXECUTION CONTEXT

GetTimeBaseInfo may be called from task level, secondary interrupt level, or hardware interrupt level.

© 1999 Apple Computer, Inc. – (Last Updated 26 March 99)