Re: Casting function pointers

KKL wrote:
I wonder how casting with function pointers work, how it "should be"
handled and how it "should not be" handled. Can anyone tell whether
the below code should work or not?

<snip>
My question is whether these kind of casting for function pointers is
valid. If valid should it work with a predictable behavior or the
behavior is undefined.


It's also important to note that function pointers are not directly compatible with data pointers - you can't necessarily convert a function pointer to a void* and back again, and expect a valid result (although it should work in practice, at least on 32-bit processors). You can't ever convert a method pointer to a function pointer (unless it's a static method).

Personally, I think phrases such as "(void ()(void)* ) funcPtr" are ugly and hard to read. Use typedefs - they make your code clearer, minimise mistakes, and make it easier to change later:

typedef void (*FVoid)(void);

int taskCreate(char* taskName, FVoid funcPtr, ....)
.

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