From 5878ee6fc41906578910f760f098452b1880b792 Mon Sep 17 00:00:00 2001
From: Gerd Moellmann <gerd@gnu.org>
Date: Wed, 25 Aug 1999 21:12:36 +0000
Subject: [PATCH] (Fforward_word): If in a mini-buffer and moving backwards,
 stop in front of the prompt to prevent accidentially moving into the
 read-only prompt.

---
 src/syntax.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/syntax.c b/src/syntax.c
index 233f798025..71a2080836 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -1214,6 +1214,17 @@ and nil is returned.")
       SET_PT (XINT (count) > 0 ? ZV : BEGV);
       return Qnil;
     }
+
+  /* If in a mini-buffer and moving backwards, stop in front of the
+     prompt if we are currently in front of it.  This prevents
+     accidentially moving into the read-only prompt.  */
+  if (INTEGERP (current_buffer->minibuffer_prompt_length))
+    {
+      int prompt_end = XFASTINT (current_buffer->minibuffer_prompt_length);
+      if (PT > prompt_end && val < prompt_end)
+	val = prompt_end;
+    }
+  
   SET_PT (val);
   return Qt;
 }
-- 
2.20.1