goinstall: better usage message

Fixes #2185.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4967046

diff --git a/src/cmd/goinstall/main.go b/src/cmd/goinstall/main.go
index acda6efbb6eac94428d23b0f6b455d34f99018ec..23b26e3832cbc6aef2d34478c6284ad051736078 100644 (file)
--- a/src/cmd/goinstall/main.go
+++ b/src/cmd/goinstall/main.go
@@ -20,8 +20,8 @@ import (
 )
 
 func usage() {
-       fmt.Fprint(os.Stderr, "usage: goinstall importpath...\n")
-       fmt.Fprintf(os.Stderr, "\tgoinstall -a\n")
+       fmt.Fprintln(os.Stderr, "usage: goinstall [flags] importpath...")
+       fmt.Fprintln(os.Stderr, "       goinstall [flags] -a")
        flag.PrintDefaults()
        os.Exit(2)
 }