From 9173a095300ad4a1d0e57b4d096c39a655753382 Mon Sep 17 00:00:00 2001
From: Andrew Gerrand <adg@golang.org>
Date: Mon, 31 Jan 2011 18:54:25 +1100
Subject: [PATCH] bufio: make Flush a no-op when the buffer is empty

R=r
CC=golang-dev
https://golang.org/cl/4119048
---
 src/pkg/bufio/bufio.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/pkg/bufio/bufio.go b/src/pkg/bufio/bufio.go
index 67b7cdb53c3..eae5c5ce975 100644
--- a/src/pkg/bufio/bufio.go
+++ b/src/pkg/bufio/bufio.go
@@ -385,6 +385,9 @@ func (b *Writer) Flush() os.Error {
 	if b.err != nil {
 		return b.err
 	}
+	if b.n == 0 {
+		return nil
+	}
 	n, e := b.wr.Write(b.buf[0:b.n])
 	if n < b.n && e == nil {
 		e = io.ErrShortWrite