From c39f3bac71af80db95b52a86bb4b16f9cb95deb6 Mon Sep 17 00:00:00 2001
From: Jilles Tjoelker <jilles@FreeBSD.org>
Date: Sun, 21 Feb 2016 18:54:17 +0000
Subject: [PATCH] sh: Optimize setprompt(0).

Avoid doing work to print an empty prompt (such as when reading scripts).
---
 bin/sh/parser.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/bin/sh/parser.c b/bin/sh/parser.c
index 53d7923f8755..d324d88a8f18 100644
--- a/bin/sh/parser.c
+++ b/bin/sh/parser.c
@@ -1930,6 +1930,8 @@ static void
 setprompt(int which)
 {
 	whichprompt = which;
+	if (which == 0)
+		return;
 
 #ifndef NO_HISTORY
 	if (!el)