1// Copyright 2016 The etcd Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15// etcdctl is a command line application that controls etcd.
16package main
17
18import (
19	"fmt"
20	"os"
21
22	"go.etcd.io/etcd/etcdctl/ctlv2"
23	"go.etcd.io/etcd/etcdctl/ctlv3"
24)
25
26const (
27	apiEnv = "ETCDCTL_API"
28)
29
30func main() {
31	apiv := os.Getenv(apiEnv)
32	// unset apiEnv to avoid side-effect for future env and flag parsing.
33	os.Unsetenv(apiEnv)
34	if len(apiv) == 0 || apiv == "3" {
35		ctlv3.Start()
36		return
37	}
38
39	if apiv == "2" {
40		ctlv2.Start()
41		return
42	}
43
44	fmt.Fprintln(os.Stderr, "unsupported API version", apiv)
45	os.Exit(1)
46}
47