/* *  Test case for assertion #1 of the sigaction system call that shows * sigaction (when used with a non-null act pointer) changes the action * for a signal. * * Steps: * 1. Initialize a global variable to indicate the signal *    handler has not been called. (A signal handler of the  *    prototype "void func(int signo);" will set the global *    variable to indicate otherwise.  * 2. Use sigaction to setup a signal handler for SIGUSR1 * 3. Raise SIGUSR1. * 4. Verify the global indicates the signal was called.*/#include <signal.h>#include "compat.h"#define NTASKS 1static pthread_t thread[NTASKS];int handler_called = 0;void handler(int signo){	handler_called = 1;}void * th_code (void * arg){	struct sigaction act;		act.sa_handler = handler;	act.sa_flags = 0;	sigemptyset(&act.sa_mask);	if (sigaction(SIGUSR1,  &act, 0) == -1) {		perror("Unexpected error while attempting to setup test "		       "pre-conditions");		return -1;	}		if (raise(SIGUSR1) == -1) {		perror("Unexpected error while attempting to setup test "		       "pre-conditions");		return -1;	}	if (handler_called) {		printf("Test PASSED\n");		return 0;	}	printf("Test FAILED\n");	return -1;	}int init_module(void){  int i;  for(i=0;i<NTASKS;i++)    pthread_create(&thread[i], NULL,th_code,(void *) i);  return 0;  }void cleanup_module(void){ int i;  for(i=0;i<NTASKS;i++)    pthread_delete_np(thread[i]);}