r305_dm/TP3/Exo5/exo5_3.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <math.h>
#include <signal.h>

#define SIZE 1000
int search(const unsigned char *t, int start, int end, int n)
{
    pid_t p;
    int i, proc, res = 0, status, partition = ceil((start + end) / n);

    for (proc = 1; proc <= n; proc++)
    {
        p = fork();
        if (p == 0)
        {
            for (i = 0 + partition * proc; i < partition * (proc + 1); i++)
            {
                if (t[i] == 0)
                {
                    exit(1);
                    kill(0, SIGTERM);
                }
            }
            exit(0);
        }
    }

    for (i = 0; i < n; i++)
    {
        wait(&status);
        if (WEXITSTATUS(status))
            res = 1;
    }
    return res;
}

int main(int argc, char *argv[])
{
    int i, n;
    unsigned char arr[SIZE];
    if (argc != 2)
    {
        printf("Usage: %s <number of children is between 1 and 100>\n", argv[0]);
        return EXIT_FAILURE;
    }

    n = (int)strtod(argv[1], NULL);
    srandom(time(NULL));

    for (i = 0; i < SIZE; i++)
        arr[i] = (unsigned char)(random() % 255) + 1;

    printf("Enter a number between 0 and %d: ", SIZE);
    scanf(" %d", &i);

    if (i >= 0 && i < SIZE)
        arr[i] = 0;

    if (search(arr, 0, SIZE - 1, n))
        printf("Found !\n");
    else
        printf("Not found !\n");
    return EXIT_SUCCESS;
}