This is a repeating timer for iOS and Mac OS. It provides similar functionality like a GCD timer, but the thread executing the timer action is a real time thread.
I developed this, because of too heavy timer deviations for a project I am developing.
It is highly recommended to read TN2169: https://developer.apple.com/library/ios/technotes/tn2169/_index.html
usage: Just add so_hptimer.c/h to your project. The repo contains an entire Xcode project with a little test app, that does measurements with a DISPATCH_SOURCE_TYPE_TIMER and a so_hptimer.
This are measurments taken on iPhone 4, iOS 7:
DISPATCH_SOURCE_TYPE_TIMER: AVG: 40.00ms MAX: 65.63ms MIN: 14.40ms STD_DEV: 2.13
so_hptimer: AVG: 40.00ms MAX: 40.15ms MIN: 39.86ms STD_DEV: 0.04
The MIT License (MIT)
(c) 2014 Ulrich Zurucker, http://sononum.net
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