BDD P. Système P. Linéaire POO G. Logiciel Simu Anglais

L3

Sujet

Faire un programme:

./a.out fichier1 fichier2

Il faut qu'il y ait deux processus qui travaillent sur le même tampon (tube) en parralèle.

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>


/
 *                  T[1]                T[0]
 *      +---------------|===============|----------+
 *      |                                          |
 *  +--------+                                 +--------+
 *  | Tampon |                                 | Tampon |
 *  +--------+                                 +--------+
 *     |                                           |
 * |Fichier 1|                                 |Fichier 2|
 *
 *     fils                                       père
 */
int main(int argc, char argv) {
  int pid, n, x, des1, des2, T[2];
  char tampon[255];
  struct stat s1;

if (argc < 3) {
    perror("Nombre d'arguments insuffisant.");
    exit(1);
  }

if (pipe(T) == -1) {
    perror("Erreur de tube.");
    exit(1);
  }

pid = fork();

if (pid < 0) {
    perror("Erreur de fork.");
    exit(1);
  }

des1 = open(argv[1], O_RDONLY);

if (des1 == -1) {
    perror("Fichier non existant.");
    exit(1);
  }

if (fstat(des1, &s1) == -1) {
    perror("Erreur de fstat");
    exit(1);
  }

des2 = open(argv[2], OWRONLY|OCREAT|OEXCL, s1.stmode);

if (pid == 0) {
    close(T[0]);
<span class="k">while</span> <span class="p">((</span><span class="n">n</span> <span class="o">=</span> <span class="n">read</span><span class="p">(</span><span class="n">des1</span><span class="p">,</span> <span class="n">tampon</span><span class="p">,</span> <span class="mi">255</span><span class="p">)))</span>
  <span class="n">write</span><span class="p">(</span><span class="n">T</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span> <span class="n">tampon</span><span class="p">,</span> <span class="n">n</span><span class="p">);</span>

<span class="n">close</span><span class="p">(</span><span class="n">T</span><span class="p">[</span><span class="mi">1</span><span class="p">]);</span>
<span class="n">exit</span><span class="p">(</span><span class="mi">0</span><span class="p">);</span>

} else {
    close(T[1]);
<span class="k">while</span> <span class="p">((</span><span class="n">n</span> <span class="o">=</span> <span class="n">read</span><span class="p">(</span><span class="n">T</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">tampon</span><span class="p">,</span> <span class="mi">255</span><span class="p">)))</span>
  <span class="n">write</span><span class="p">(</span><span class="n">des2</span><span class="p">,</span> <span class="n">tampon</span><span class="p">,</span> <span class="n">n</span><span class="p">);</span>

<span class="n">close</span><span class="p">(</span><span class="n">T</span><span class="p">[</span><span class="mi">0</span><span class="p">]);</span>
<span class="n">close</span><span class="p">(</span><span class="n">des1</span><span class="p">);</span>
<span class="n">close</span><span class="p">(</span><span class="n">des2</span><span class="p">);</span>
<span class="n">wait</span><span class="p">(</span><span class="o">&amp;</span><span class="n">x</span><span class="p">);</span>

}
}