>Use the bitwise AND operator & to check for a selected bitmask enumeration value.
You should take care if you store result of this in a BOOL (or pass it to a method or function that takes a BOOL). BOOL is only char big and plenty of common Cocoa bitmasks don't have any bits set in that range. For example NSEventMaskEndGesture is (1<<20).
NSEventMask mask = NSEventMaskEndGesture;
BOOL end = mask & NSEventMaskEndGesture;
if (!end) NSLog(@"Oops");
Isn't this applicable to any kind of bitmask, and not just Obj-C?
I suppose that Cocoa uses bitmasks fairly often, but this article could have been titled "Working With Bitmasks in C" and it would have been just as accurate.
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[ 4.8 ms ] story [ 28.1 ms ] threadYou should take care if you store result of this in a BOOL (or pass it to a method or function that takes a BOOL). BOOL is only char big and plenty of common Cocoa bitmasks don't have any bits set in that range. For example NSEventMaskEndGesture is (1<<20).
Also works for pointers:
I suppose that Cocoa uses bitmasks fairly often, but this article could have been titled "Working With Bitmasks in C" and it would have been just as accurate.