cm processus

tp/tp3/src/copy_on_write.c

@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+#define N 8*1024*1024 
+
+char tab[N];
+
+int main(void)
+{
+	for (int i = 0; i < N; i++)
+		tab[i] = (char)i;
+
+	printf("Avant fork : tab = %p\n", (void *)tab);
+
+	pid_t pid = fork();
+
+	if (pid < 0) {
+		perror("fork");
+		exit(EXIT_FAILURE);
+	}
+
+	if (pid == 0) {
+		printf("Fils : tab = %p, tab[5000] = %d\n",
+				(void *)(tab+5000), tab[5000]);
+		printf("FILS PID = %d\n", getpid());
+		getchar();
+
+		tab[5000] = 42;
+		printf("-> modification\n");
+		getchar();
+
+		printf("Fils après modification : tab[5000] = %d\n",
+				tab[5000]);
+
+		exit(EXIT_SUCCESS);
+	}
+	else {
+		sleep(1);
+
+		printf("Père : tab = %p, tab[5000] = %d\n",
+				(void *)tab, tab[5000]);
+
+		wait(NULL);
+	}
+
+	return 0;
+}