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.unix; 19 20 import java.io.IOException; 21 import org.apache.commons.net.bsd.RCommandClient; 22 23 import examples.util.IOUtil; 24 25 /*** 26 * This is an example program demonstrating how to use the RCommandClient 27 * class. This program connects to an rshell daemon and requests that the 28 * given command be executed on the server. It then reads input from stdin 29 * (this will be line buffered on most systems, so don't expect character 30 * at a time interactivity), passing it to the remote process and writes 31 * the process stdout and stderr to local stdout. 32 * <p> 33 * On Unix systems you will not be able to use the rshell capability 34 * unless the process runs as root since only root can bind port addresses 35 * lower than 1024. 36 * <p> 37 * Example: java rshell myhost localusername remoteusername "ps -aux" 38 * <p> 39 * Usage: rshell <hostname> <localuser> <remoteuser> <command> 40 * <p> 41 ***/ 42 43 // This class requires the IOUtil support class! 44 public final class rshell 45 { 46 47 public static void main(String[] args) 48 { 49 String server, localuser, remoteuser, command; 50 RCommandClient client; 51 52 if (args.length != 4) 53 { 54 System.err.println( 55 "Usage: rshell <hostname> <localuser> <remoteuser> <command>"); 56 System.exit(1); 57 return ; // so compiler can do proper flow control analysis 58 } 59 60 client = new RCommandClient(); 61 62 server = args[0]; 63 localuser = args[1]; 64 remoteuser = args[2]; 65 command = args[3]; 66 67 try 68 { 69 client.connect(server); 70 } 71 catch (IOException e) 72 { 73 System.err.println("Could not connect to server."); 74 e.printStackTrace(); 75 System.exit(1); 76 } 77 78 try 79 { 80 client.rcommand(localuser, remoteuser, command); 81 } 82 catch (IOException e) 83 { 84 try 85 { 86 client.disconnect(); 87 } 88 catch (IOException f) 89 {} 90 e.printStackTrace(); 91 System.err.println("Could not execute command."); 92 System.exit(1); 93 } 94 95 96 IOUtil.readWrite(client.getInputStream(), client.getOutputStream(), 97 System.in, System.out); 98 99 try 100 { 101 client.disconnect(); 102 } 103 catch (IOException e) 104 { 105 e.printStackTrace(); 106 System.exit(1); 107 } 108 109 System.exit(0); 110 } 111 112 } 113