disable all interrupts when acquiring lock

user program that makes a blocking system call

1 files changed, 8 insertions, 0 deletions

diff --git a/ulib.c b/ulib.c
index d99acdd..5061732 100644
--- a/ulib.c
+++ b/ulib.c
@@ -56,3 +56,11 @@ close(int fd)
   asm("mov $8, %eax");
   asm("int $48");
 }
+
+int
+block(void)
+{
+  asm("mov $9, %eax");
+  asm("int $48");
+}
+