iPhone Quartz 2D: CGContextSetLineJoin equivalent for CGMutablePathRef?

What is the CGMutablePathRef equivalent of CGContextSetLineJoin? CGContextSetLineJoin works directly on the graphics c开发者_JAVA技巧ontext, so requires a CGContextRef parameter, which I do not have since I'm working with CGMutablePathRef. I can't find anything in CGPath.h that does CGContextSetLineJoin's job.

Thank you.

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Using CGMutablePathRef, you are just defining a path. It's not until you paint the path that you can use functions like CGContextSetLineJoin. Cf. Apple's documentation:

You must call a painting function to fill or stroke the path because creating a path does not draw the path.