diff --git a/src/nnn.c b/src/nnn.c
index a8f82edb..ef20b13d 100644
--- a/src/nnn.c
+++ b/src/nnn.c
@@ -4326,9 +4326,11 @@ static void readpipe(int fd, char **path, char **lastname, char **lastdir)
 
 	if (g_buf[0] == '+')
 		ctx = (char)(get_free_ctx() + 1);
+	else if (g_buf[0] < '0')
+		return;
 	else {
 		ctx = g_buf[0] - '0';
-		if (ctx < 0 || ctx > CTX_MAX)
+		if (ctx > CTX_MAX)
 			return;
 	}