jehanne/qa/lib/newlib/200-signals.c

79 lines
1.5 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
void sighup(); /* routines child will call upon sigtrap */
void sigint();
void sigquit();
int
main() {
int pid, p[2], child, cstatus;
char dummy[1];
/* get child process */
if(pipe(p)){
perror("pipe");
exit(1);
}
if ((pid = fork()) < 0) {
perror("fork");
exit(2);
}
if (pid == 0) {
printf("\nI am the new child!\n\n");
signal(SIGHUP,sighup); /* set function calls */
signal(SIGINT,sigint);
signal(SIGQUIT, sigquit);
printf("\nChild going to loop...\n\n");
close(p[1]);
close(p[0]);
for(;;); /* loop for ever */
}
else /* parent */
{
close(p[1]);
if(read(p[0], &dummy, 1) > 0){
printf("sync read received data");
exit(EXIT_FAILURE);
}
close(p[0]);
printf("\nPARENT: sending SIGHUP\n\n");
kill(pid,SIGHUP);
sleep(3); /* pause for 3 secs */
printf("\nPARENT: sending SIGINT\n\n");
kill(pid,SIGINT);
sleep(3); /* pause for 3 secs */
printf("\nPARENT: sending SIGQUIT\n\n");
kill(pid,SIGQUIT);
child = wait(&cstatus);
if(child == pid && cstatus == 0)
exit(0);
else
{
printf("PARENT: child exited with status %d\n", cstatus);
exit(1);
}
}
}
void sighup() {
signal(SIGHUP,sighup); /* reset signal */
printf("CHILD: I have received a SIGHUP\n");
}
void sigint() {
signal(SIGINT,sigint); /* reset signal */
printf("CHILD: I have received a SIGINT\n");
}
void sigquit() {
printf("My DADDY has Killed me!!!\n");
exit(0);
}