Signal Handling Question:
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What is the output of this program?

#include<stdio.h>
#include<signal.h>

void response (int);
void response (int sig_no)
{
printf("%sn",sys_siglist[sig_no]);
}
int main()
{
pid_t child;
int status;
child = fork();
switch(child){
case -1:
perror("fork");
case 0:
break;
default :
signal(SIGCHLD,response);
wait(&status);
break;
}
}
a) this program will print nothing
b) this program will print "Child Exited"
c) segmentation fault
d) none of the mentioned

Linux Signal Handling Interview Question
Linux Signal Handling Interview Question

Answer:

b) this program will print "Child Exited"
Explanation:
The child process sends SIGCHILD signal to its parent as it terminates.
Output:
[root@localhost google]# gcc -o san san.c
[root@localhost google]# ./san
Child exited
[root@localhost google]#

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Previous QuestionNext Question
Which one of the following is not true about this program?

#include<stdio.h>
#include<signal.h>

void response (int);
void response (int signo)
{
printf("%sn",sys_siglist[signo]);
signal(SIGSEGV,SIG_IGN);
}
int main()
{
signal (SIGSEGV,response);
char *str;
*str = 10;
return 0;
}
a) kernel sends SIGSEGV signal to a process as segmentation fault occurs
b) in this process signal handler will execute only one time of recieving the signal SIGSEGV
c) both (a) and (b)
d) none of the mentioned		In this program

#include<stdio.h>
#include<signal.h>
#include<stdlib.h>

int main()
{
pid_t child;
child=fork();
switch(child){
case -1 :
perror("fork");
exit(1);
case 0 :
while(1){
printf("Child Processn");
sleep(1);
}
break;
default :
sleep(5);
kill(child,SIGINT);
printf("The child process has been killed by the parent processn");
break;
}
return 0;
}
a) the child process kills the parent process
b) the parent process kills the child process
c) both the processes are killed by each other
d) none of the mentioned