2014/10/15 下午 10:11:14

iphone Programming Glossary: mach_timebase_info

What is mach_absolute_time based on on iPhone

http://stackoverflow.com/questions/1450737/what-is-mach-absolute-time-based-on-on-iphone

otherwise known as uptime . In order to get it in a human readable form you have to modify it by the result from mach_timebase_info a ratio which will return billionth of seconds or nanoseconds . To make this more usable I use a function like the one below.. like the one below #include mach mach_time.h int getUptimeInMilliseconds const int64_t kOneMillion 1000 1000 static mach_timebase_info_data_t s_timebase_info if s_timebase_info.denom 0 void mach_timebase_info s_timebase_info mach_absolute_time returns billionth.. const int64_t kOneMillion 1000 1000 static mach_timebase_info_data_t s_timebase_info if s_timebase_info.denom 0 void mach_timebase_info s_timebase_info mach_absolute_time returns billionth of seconds so divide by one million to get milliseconds return int..

How do I accurately time how long it takes to call a function on the iPhone?

http://stackoverflow.com/questions/646815/how-do-i-accurately-time-how-long-it-takes-to-call-a-function-on-the-iphone

#import mach mach_time.h uint64_t startTime 0 uint64_t endTime 0 uint64_t elapsedTime 0 uint64_t elapsedTimeNano 0 mach_timebase_info_data_t timeBaseInfo mach_timebase_info timeBaseInfo startTime mach_absolute_time do something here endTime mach_absolute_time.. 0 uint64_t endTime 0 uint64_t elapsedTime 0 uint64_t elapsedTimeNano 0 mach_timebase_info_data_t timeBaseInfo mach_timebase_info timeBaseInfo startTime mach_absolute_time do something here endTime mach_absolute_time elapsedTime endTime startTime elapsedTimeNano..

CoreAudio AudioTimeStamp.mHostTime clock frequency?

http://stackoverflow.com/questions/675626/coreaudio-audiotimestamp-mhosttime-clock-frequency

to sleep. So how do you convert those ticks into a real time value The file of above also defines a structure named mach_timebase_info struct mach_timebase_info uint32_t numer uint32_t denom You can get the correct values for this structure using the function.. convert those ticks into a real time value The file of above also defines a structure named mach_timebase_info struct mach_timebase_info uint32_t numer uint32_t denom You can get the correct values for this structure using the function mach_timebase_info e.g... mach_timebase_info uint32_t numer uint32_t denom You can get the correct values for this structure using the function mach_timebase_info e.g. kern_return_t kerror mach_timebase_info_data_t tinfo kerror mach_timebase_info tinfo if kerror KERN_SUCCESS TODO handle..