what does this statement represent [func ptr]

Question

I came across a strange function pointer,

void * (*f1(void(*f2)(void)))(int ) ;

What does the f1 represent here ?

This explains it very well in [ another question][1] [1]: http://stackoverflow.com/questions/20357106/what-does-c-expression-voidvoid0-mean/20357286#20357286 — Hemant Kumar, Sep 24 '15 at 05:36

molbdnilo · Accepted Answer · 2015-09-24T05:52:01.283

4

T (*f(U))(V)

declares f as a function which takes a U and returns a pointer to a function from V to T (i.e. a T (*)(V)).

So f1 is a function that takes a void (*)(void) and returns a void* (*)(int).

Naming the types makes it more readable:

typedef void (*parameter)();
typedef void* (*result)(int);
result f1(parameter f2);

(The name "f2" serves no purpose except for helping the human reading the code interpret it.)

edited Sep 24 '15 at 05:52

answered Sep 24 '15 at 05:13

molbdnilo

@Prakash You can think of it that way, but it's not valid syntax. Naming the types using typedefs helps. – molbdnilo Sep 24 '15 at 05:49

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