Parse sgi stl function static void (* _ set_malloc_handler (void (* _ f )()))()

Parse sgi stl function static void (* _ set_malloc_handler (void (* _ f )()))()

static void (* __set_malloc_handler(void (*__f)()))(){    void (* __old)() = __malloc_alloc_oom_handler;    __malloc_alloc_oom_handler = __f;    return(__old);}

First, you must know the function expression of the function pointer as the parameter and the return function pointer (see Function
Pointer ).
Therefore, void (* set_malloc_handler () indicates that set_malloc_handler is a function pointer in the form of void (* f) () returned value.
Second, void (* _ f) () is just a function parameter.
In conclusion, void (* _ set_malloc_handler (void (* _ f) () is a function that accepts a form of void (* _ F) () function pointer as a parameter,
And return a function pointer in the form of void (* _ f. The easy-to-understand format is

typedef void(*pt2Func)();pt2Func __set_malloc_handler( void (*__f)() )  {    void (* __old)() = __malloc_alloc_oom_handler;    __malloc_alloc_oom_handler = __f;    return(__old);  }