From f0509623ce214615bab4f0d5a6e087c7e7934d2f Mon Sep 17 00:00:00 2001
From: Alasdair Kergon <agk@redhat.com>
Date: Wed, 23 Nov 2011 01:34:38 +0000
Subject: [PATCH] Move y/n prompts to stderr and repeat if response has both
 'n' and 'y'.

(Note that in a future release we might make this stricter and insist
on exactly 'y' or 'n'.)
---
 WHATS_NEW             |  1 +
 lib/display/display.c | 16 +++++++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/WHATS_NEW b/WHATS_NEW
index 1551ebcbb..d0540fb90 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.89 - 
 ==================================
+  Move y/n prompts to stderr and repeat if response has both 'n' and 'y'.
   Replace the unit testing framework with CUnit (--enable-testing).
   Fix dmeventd snapshot monitoring when multiple extensions were involved.
   Don't ignore configure --mandir and --infodir.
diff --git a/lib/display/display.c b/lib/display/display.c
index 6e61dc827..298abc950 100644
--- a/lib/display/display.c
+++ b/lib/display/display.c
@@ -850,9 +850,10 @@ char yes_no_prompt(const char *prompt, ...)
 	do {
 		if (c == '\n' || !c) {
 			va_start(ap, prompt);
-			vprintf(prompt, ap);
+			vfprintf(stderr, prompt, ap);
 			va_end(ap);
-			fflush(stdout);
+			fflush(stderr);
+			ret = 0;
 		}
 
 		if ((c = getchar()) == EOF) {
@@ -861,9 +862,14 @@ char yes_no_prompt(const char *prompt, ...)
 		}
 
 		c = tolower(c);
-		if ((c == 'y') || (c == 'n'))
-			ret = c;
-	} while (!ret || c != '\n');
+		if ((c == 'y') || (c == 'n')) {
+			/* If both 'y' and 'n' given, begin again. */
+			if (ret && c != ret)
+				ret = -1;
+			else
+				ret = c;
+		}
+	} while (ret < 1 || c != '\n');
 
 	sigint_restore();