-signal_handler_t sys_signal (int signal_number, signal_handler_t action);
-int sys_sigpause (sigset_t new_mask);
-sigset_t sys_sigblock (sigset_t new_mask);
-sigset_t sys_sigunblock (sigset_t new_mask);
-sigset_t sys_sigsetmask (sigset_t new_mask);
+signal_handler_t sys_signal (/*int signal_number, signal_handler_t action*/);
+int sys_sigpause (/*sigset_t new_mask*/);
+sigset_t sys_sigblock (/*sigset_t new_mask*/);
+sigset_t sys_sigunblock (/*sigset_t new_mask*/);
+sigset_t sys_sigsetmask (/*sigset_t new_mask*/);