more tools

tools/lookpath.go

@@ -0,0 +1,44 @@
+// Copyright 2014 <chaishushan{AT}gmail.com>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ingore
+
+// Lookpath is a simple which.
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Printf(`Usage: lookpath COMMAND [...]
+Write the full path of COMMAND(s) to standard output.
+
+Report bugs to <chaishushan@gmail.com>.
+`)
+		os.Exit(0)
+	}
+	for i := 1; i < len(os.Args); i++ {
+		path, err := exec.LookPath(os.Args[i])
+		if err != nil {
+			fmt.Printf("lookpath: no %s in (%v)\n", os.Args[i], GetEnv("PATH"))
+			os.Exit(0)
+		}
+		fmt.Println(path)
+	}
+}
+
+func GetEnv(key string) string {
+	key = strings.ToUpper(key) + "="
+	for _, env := range os.Environ() {
+		if strings.HasPrefix(strings.ToUpper(env), key) {
+			return env[len(key):]
+		}
+	}
+	return ""
+}