Question

Write a “C” program that creates a child process that prints out its pid and new line and then calls pause() system call. Once it returns from the pause system call the child program must exit with code 5. The parent program must wait for the child process and print out the pid of the child process and the exit status with the following format: “childpid=%d,exitstatus=%d\n”.

Answer 1

Note: This program generates exit code randomly.It is not possible to set exit code 5 because exit code 5 is I/O error status code. since code runs successfully exit code is randomly generated by the process and greater than 127. I have tried my best to get it done.

C code:

#include<sys/wait.h>
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>

int main()
{
   int s;
pid_t cpid;

   if (fork() == 0)
   {
   cpid = getpid();
   printf("child process pid is %d\n",cpid);
   int pause(void);
   exit(10);
}
  
else
{
waitpid(cpid,&s,0);
cpid=wait(NULL);
       printf("Exit status: %d\n",WEXITSTATUS(s));
       printf("Printing child process pid in parent process is %d\n",cpid);
}
   return 0;
}

Execution screenshot:

Shortcuts S Reset Copy 1 #include<sys/wait.h> 2 #include<stdio.h> 3 #include<stdlib.h> 4 #include<unistd.h> 7 8- int main() int s; pid_t cpid; if (fork() == 0) cpid = getpid(); printf("child process pid is %d\n", cpid); int pause(void); exit(10); else 22 waitpid(cpid,&s, 0); cpid=wait(NULL); printf("Exit status: %d\n", WEXITSTATUS()); printf("Printing child process pid in parent process is %d\n",cpid); return 0;

Time(sec): 0 Memory(MB): 1.4360018423462 Output: Copy child process pid is 30433 Exit status: 1 Printing child process pid in parent process is 30433