chap3

bac2/os/chap3/ex3.c

@@ -0,0 +1,25 @@
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <time.h>
+
+#define printvi(X) printf("%s = %d\n", #X, X);
+
+int main(void)
+{
+	pid_t f = fork();
+	if(f == 0){
+		srand(time(NULL));
+		int delay = 1 + rand() % 10;
+		int value = rand() % 256;
+		printvi(delay);
+		printvi(value);
+		sleep(delay);
+		return value;
+	}
+
+	int child_ret = 0;
+	wait(&child_ret);
+	printvi(WEXITSTATUS(child_ret));
+}