Dear All, I want to know is there any method/API to know whether there is previous signal handler for specific signal no. Example: In below case we install 3 handler. So my question is if before calling signal (SIGUSR1, handler2); is there any way i can get info that there is "handler1" already install with SIGUSR1. signal (SIGUSR1, handler1); signal (SIGUSR1, handler2); signal (SIGUSR1, handler3); #include <stdio.h> #include <stdlib.h> #include <pthread.h> #include <signal.h> void *func (); void handler1 () { printf ("\nIn handler 1\n"); } void handler2 () { printf ("\nIn handler 2\n"); } void handler3 () { printf ("\nIn handler 3\n"); } int main () { int err=-1; pthread_t t1,t2; signal (SIGUSR1, handler1); sleep(5); signal (SIGUSR1, handler2); sleep(5); signal (SIGUSR1, handler3); sleep(5); pthread_create (&t1, NULL, &func, NULL); sleep(20); return 0; } void *func() { while (1) usleep(10); }