Merge branch 'cow' into net

Conflicts:
	.gitignore
	Makefile
	conf/lab.mk
	kernel/defs.h
	kernel/syscall.c
	kernel/vm.c
	user/pingpong.c
	user/user.h
	user/usys.pl

1 files changed, 22 insertions, 0 deletions

diff --git a/user/sleep.c b/user/sleep.c
new file mode 100644
index 0000000..961f558
--- /dev/null
+++ b/user/sleep.c
@@ -0,0 +1,22 @@
+#include "kernel/types.h"
+#include "user/user.h"
+
+int
+main(int argc, char* argv[])
+{
+  uint sec = 0;
+
+  if (argc <= 1) {
+    fprintf(2, "usage: sleep [time (ticks)]\n");
+    exit(1);
+  }
+  sec = atoi(argv[1]);
+
+  sleep(sec);
+
+  if (argc <= 2) {
+    exit(0);
+  }
+
+  exit(0);
+}