1 files changed, 15 insertions, 0 deletions

diff --git a/pintos-progos/tests/userprog/wait-twice.c b/pintos-progos/tests/userprog/wait-twice.c
new file mode 100644
index 0000000..785e684
--- /dev/null
+++ b/pintos-progos/tests/userprog/wait-twice.c
@@ -0,0 +1,15 @@
+/* Wait for a subprocess to finish, twice.
+   The first call must wait in the usual way and return the exit code.
+   The second wait call must return -1 immediately. */
+
+#include <syscall.h>
+#include "tests/lib.h"
+#include "tests/main.h"
+
+void
+test_main (void) 
+{
+  pid_t child = exec ("child-simple");
+  msg ("wait(exec()) = %d", wait (child));
+  msg ("wait(exec()) = %d", wait (child));
+}