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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  
18  package examples;
19  
20  import java.io.IOException;
21  import org.apache.commons.net.bsd.RLoginClient;
22  
23  /***
24   * This is an example program demonstrating how to use the RLoginClient
25   * class. This program connects to an rlogin daemon and begins to
26   * interactively read input from stdin (this will be line buffered on most
27   * systems, so don't expect character at a time interactivity), passing it
28   * to the remote login process and writing the remote stdout and stderr
29   * to local stdout.  If you don't have .rhosts or hosts.equiv files set up,
30   * the rlogin daemon will prompt you for a password.
31   * <p>
32   * On Unix systems you will not be able to use the rshell capability
33   * unless the process runs as root since only root can bind port addresses
34   * lower than 1024.
35   * <p>
36   * JVM's using green threads will likely have problems if the rlogin daemon
37   * requests a password.  This program is merely a demonstration and is
38   * not suitable for use as an application, especially given that it relies
39   * on line buffered input from System.in.  The best way to run this example
40   * is probably from a Win95 dos box into a Unix host.
41   * <p>
42   * Example: java rlogin myhost localusername remoteusername vt100
43   * <p>
44   * Usage: rlogin <hostname> <localuser> <remoteuser> <terminal>
45   * <p>
46   ***/
47  
48  // This class requires the IOUtil support class!
49  public final class rlogin
50  {
51  
52      public static final void main(String[] args)
53      {
54          String server, localuser, remoteuser, terminal;
55          RLoginClient client;
56  
57          if (args.length != 4)
58          {
59              System.err.println(
60                  "Usage: rlogin <hostname> <localuser> <remoteuser> <terminal>");
61              System.exit(1);
62              return ; // so compiler can do proper flow control analysis
63          }
64  
65          client = new RLoginClient();
66  
67          server = args[0];
68          localuser = args[1];
69          remoteuser = args[2];
70          terminal = args[3];
71  
72          try
73          {
74              client.connect(server);
75          }
76          catch (IOException e)
77          {
78              System.err.println("Could not connect to server.");
79              e.printStackTrace();
80              System.exit(1);
81          }
82  
83          try
84          {
85              client.rlogin(localuser, remoteuser, terminal);
86          }
87          catch (IOException e)
88          {
89              try
90              {
91                  client.disconnect();
92              }
93              catch (IOException f)
94              {}
95              e.printStackTrace();
96              System.err.println("rlogin authentication failed.");
97              System.exit(1);
98          }
99  
100 
101         IOUtil.readWrite(client.getInputStream(), client.getOutputStream(),
102                          System.in, System.out);
103 
104         try
105         {
106             client.disconnect();
107         }
108         catch (IOException e)
109         {
110             e.printStackTrace();
111             System.exit(1);
112         }
113 
114         System.exit(0);
115     }
116 
117 }
118