--- src/gplt_x11.c
+++ src/gplt_x11.c	2006-01-31 11:09:17.000000000 +0000
@@ -1103,8 +1103,8 @@
 static int
 read_input()
 {
-    static int rdbuf_size = 10 * Nbuf;
-    static char rdbuf[10 * Nbuf];
+    const int rdbuf_size = 10 * Nbuf;
+    static char rdbuf[rdbuf_size+1];
     static int total_chars;
     static int rdbuf_offset;
     static int buf_offset;