13b.c

/*
============================================================================
Name : 13b
Author : Piyush Singh
Description : Write two programs: first program is waiting to catch SIGSTOP signal, the second program
will send the signal (using kill system call). Find out whether the first program is able to catch
the signal or not.
Date: 19th Sep, 2025.
============================================================================
*/


// Program 2: Sender — sends SIGSTOP to another process
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>

int main() 
{
    pid_t target_pid;

    // Ask user for the PID of the receiver program
    printf("🎯 Enter the PID of the receiver process: ");
    scanf("%d", &target_pid);

    // Send SIGSTOP to the target process
    if (kill(target_pid, SIGSTOP) == 0)
        printf("✅ Sent SIGSTOP to process %d. It should now be paused.\n", target_pid);
    else 
        perror("❌ Failed to send SIGSTOP");

    return 0;
}

/*
Output:
╰─ ./13b                                                                     ─╯
🎯 Enter the PID of the receiver process: 21084
✅ Sent SIGSTOP to process 21084. It should now be paused.
*/