diff --git a/src/os_unix.c b/src/os_unix.c
index f0a5621..c78e7bf 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -511,7 +511,7 @@
 		|| interrupted
 #endif
 		|| wait_time > 0
-		|| !did_start_blocking)
+		|| (wtime < 0 && !did_start_blocking))
 	    continue;
 
 	/* no character available or interrupted */
diff --git a/src/version.c b/src/version.c
index 7d2cf27..3ebe8a6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    512,
+/**/
     511,
 /**/
     510,