StreamJockey

Cat Demands Equal Time

Our cat Hop-a-long (or as my daughter calls her Bennie after Ben Affleck) decided I was paying too much attention to iPhone development and documents.

Blog posted here.

Big Nerd Ranch Weblog » How to Time

I was asked three times last week how I find how long an activity takes on the Mac and the iPhone.  Here is the most accurate method that I know of:

#import uint64_t start = mach_absolute_time(); 
// do stuff to be timed 
uint64_t end = mach_absolute_time(); 
uint64_t elapsed = end - start; 
mach_timebase_info_data_t info; 
if (mach_timebase_info (&info) != KERN_SUCCESS) { 
  printf ("mach_timebase_info failed\n"); }
uint64_t nanosecs = elapsed * info.numer / info.denom;
uint64_t millisecs = nanosecs / 1000000;

As you use this, remember that the elapsed time for a given function will vary with the load the system is under.

via weblog.bignerdranch.com

The "timing" couldn't be better - I was just researching this topic last week.

mikeash.com: Friday Q&A 2009-11-13: Dangerous Cocoa Calls

First, let me clarify what I mean by a dangerous call. I don't mean something that is obviously dangerous, like -[NSFileManager removeFileAtPath:handler:]. That call is dangerous because you could use it to wipe the user's entire hard drive, but it's not interesting, because it's obvious that it can do this. Instead, I'm going to cover calls which are subtly dangerous, things which you might easily use in an innocent manner, only to discover later that bad things can occur.

via www.mikeash.com