os slip7

Q.1 Write a program to create a child process using fork().The parent should goto sleep state and child process should begin its execution. In the child process, use execl() to execute the
“ls” command.
ANSWER-1

#include <stdio.h>
#include <unistd.h>
int main() {
pid_t child_pid = fork();
if (child_pid == 0) {
execl("/bin/ls", "ls", (char *)NULL);
} else if (child_pid > 0) {
sleep(5);
} else {
perror("Fork failed");
return 1;}
return 0;}

Q.2 Write the simulation program using FCFS. The arrival time and first CPU bursts of different jobs should be input to the system. Assume the fixed I/O waiting time (2 units). The next
CPU burst should be generated using random function. The output should give the Gantt chart, Turnaround Time and Waiting time for each process and average times
ANSWER-2

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main() {
int n; srand(time(NULL));
printf("Enter the number of processes: "); scanf("%d", &n);
float tTAT = 0, tWT = 0, t = 0;
for (int i = 0; i < n; i++) {
int burst = rand() % 10 + 1;
t += burst + 2;
printf("P%d %d %d\n", i + 1, (int)t, (int)t - burst);
tTAT += t;
tWT += t - burst;}
printf("Avg TAT: %.2f\nAvg WT: %.2f\n", tTAT / n, tWT / n);
return 0;
}