Autorelease for CGMutablePathRef?
I am developing for iphone. I want to creating a mutable path via CGPathCreateMutable(), and I want to return it out of the function which creates it. I'm suppose to call a CGPathRelease() when I'm done with it. But since I'm returning it I wish to autorelease it. Since Quartz path is a C code (and doesn't look like an objective C object), is it correct that I cannot call autorelease on it?
Edit: For others who stumble upon t开发者_Python百科his question, the below advise is for C functions returning Core foundation objects only. For objective C methods returning Core foundation objects, see Ownership regarding to returned Quartz objects
Correct. Autorelease pools exist in the Foundation layer and above (AppKit/UIKit, etc). They don't exist for CoreFoundation/CoreGraphics objects.
The simple way around this is to rename your function. If your function is currently named:
CGMutablePathRef myAwesomePath(params...);
Then you should rename it to:
CGMutablePathRef createMyAwesomePath(params...);
so that you are safe to return an object with a +1 retain count by following the Create rule.
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