diff --git a/src/serial.c b/src/serial.c
index e489660..8683c18 100644
--- a/src/serial.c
+++ b/src/serial.c
@@ -151,7 +151,7 @@ int ser_get_control_lines(int fd)
 
 int ser_set_control_lines(int fd, int state)
 {
-  unsigned int status;
+  int status;
 
 
   if (0 > (status = ser_get_control_lines(fd))) {