在iOS (objective-C)中将mach_absolute_time转换为(纳米)秒

#include <mach/mach_time.h>

uint64_t machToNanoSeconds(uint64_t machTime) {
    static mach_timebase_info_data_t timebaseInfo;
    if (timebaseInfo.denom == 0) {
        (void) mach_timebase_info(&timebaseInfo);
    }
    return machTime * timebaseInfo.numer / timebaseInfo.denom;
}

uint64_t machTime = mach_absolute_time();
uint64_t nanoSeconds = machToNanoSeconds(machTime);
NSLog(@"转换后的纳秒数：%llu", nanoSeconds);