C declaration from standard signal Library

Question

So can someone explain what this is supposed to do:

void (*signal(int sig, void (*func)(int)) ) (int);

It is a definition taken from the st

Answer 1

The man page makes this declaration easier to understand by introducing a typedef as:

typedef void (*sighandler_t)(int);

sighandler_t signal(int signum, sighandler_t handler);

sighandler_t is defined as a pointer to a function that accepts an int and returns void.

signal is a function that accepts an int (signal number) and a function pointer and returns a function pointer.