--- a/loadtools/ttypassthru.c	Thu Oct 31 05:50:06 2013 +0000
+++ b/loadtools/ttypassthru.c	Thu Oct 31 06:56:31 2013 +0000
@@ -20,6 +20,35 @@
 static struct termios saved_termios, my_termios;
 
 static void
+safe_output(buf, cc)
+	u_char *buf;
+{
+	int i, c;
+
+	for (i = 0; i < cc; i++) {
+		c = buf[i];
+		if (c == '\r' || c == '\n' || c == '\t' || c == '\b') {
+			putchar(c);
+			continue;
+		}
+		if (c & 0x80) {
+			putchar('M');
+			putchar('-');
+			c &= 0x7F;
+		}
+		if (c < 0x20) {
+			putchar('^');
+			putchar(c + '@');
+		} else if (c == 0x7F) {
+			putchar('^');
+			putchar('?');
+		} else
+			putchar(c);
+	}
+	fflush(stdout);
+}
+
+static void
 loop()
 {
 	char buf[BUFSIZ];
@@ -55,7 +84,7 @@
 				fprintf(stderr, "EOF/error on target tty\n");
 				exit(1);
 			}
-			write(1, buf, cc);
+			safe_output(buf, cc);
 		}
 	}
 }