simple_time: include unistd.h for sleep(3)

diff --git a/simple_time.c b/simple_time.c
index eea422f..86b92f9 100644 (file)
--- a/simple_time.c
+++ b/simple_time.c
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <time.h>
+#include <unistd.h>
 
 /* Prints a time on a single line of the console.
  * I wrote this app so that I could measure times by repeatedly pressing