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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package examples;
18  
19  import java.io.IOException;
20  import org.apache.commons.net.bsd.RLoginClient;
21  
22  /***
23   * This is an example program demonstrating how to use the RLoginClient
24   * class. This program connects to an rlogin daemon and begins to
25   * interactively read input from stdin (this will be line buffered on most
26   * systems, so don't expect character at a time interactivity), passing it
27   * to the remote login process and writing the remote stdout and stderr
28   * to local stdout.  If you don't have .rhosts or hosts.equiv files set up,
29   * the rlogin daemon will prompt you for a password.
30   * <p>
31   * On Unix systems you will not be able to use the rshell capability
32   * unless the process runs as root since only root can bind port addresses
33   * lower than 1024.
34   * <p>
35   * JVM's using green threads will likely have problems if the rlogin daemon
36   * requests a password.  This program is merely a demonstration and is
37   * not suitable for use as an application, especially given that it relies
38   * on line buffered input from System.in.  The best way to run this example
39   * is probably from a Win95 dos box into a Unix host.
40   * <p>
41   * Example: java rlogin myhost localusername remoteusername vt100
42   * <p>
43   * Usage: rlogin <hostname> <localuser> <remoteuser> <terminal>
44   * <p>
45   ***/
46  
47  // This class requires the IOUtil support class!
48  public final class rlogin
49  {
50  
51      public static final void main(String[] args)
52      {
53          String server, localuser, remoteuser, terminal;
54          RLoginClient client;
55  
56          if (args.length != 4)
57          {
58              System.err.println(
59                  "Usage: rlogin <hostname> <localuser> <remoteuser> <terminal>");
60              System.exit(1);
61              return ; // so compiler can do proper flow control analysis
62          }
63  
64          client = new RLoginClient();
65  
66          server = args[0];
67          localuser = args[1];
68          remoteuser = args[2];
69          terminal = args[3];
70  
71          try
72          {
73              client.connect(server);
74          }
75          catch (IOException e)
76          {
77              System.err.println("Could not connect to server.");
78              e.printStackTrace();
79              System.exit(1);
80          }
81  
82          try
83          {
84              client.rlogin(localuser, remoteuser, terminal);
85          }
86          catch (IOException e)
87          {
88              try
89              {
90                  client.disconnect();
91              }
92              catch (IOException f)
93              {}
94              e.printStackTrace();
95              System.err.println("rlogin authentication failed.");
96              System.exit(1);
97          }
98  
99  
100         IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
101                          System.in, System.out);
102 
103         try
104         {
105             client.disconnect();
106         }
107         catch (IOException e)
108         {
109             e.printStackTrace();
110             System.exit(1);
111         }
112 
113         System.exit(0);
114     }
115 
116 }
117