001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018 package examples.unix; 019 020 import java.io.IOException; 021 import org.apache.commons.net.bsd.RCommandClient; 022 023 import examples.util.IOUtil; 024 025 /*** 026 * This is an example program demonstrating how to use the RCommandClient 027 * class. This program connects to an rshell daemon and requests that the 028 * given command be executed on the server. It then reads input from stdin 029 * (this will be line buffered on most systems, so don't expect character 030 * at a time interactivity), passing it to the remote process and writes 031 * the process stdout and stderr to local stdout. 032 * <p> 033 * On Unix systems you will not be able to use the rshell capability 034 * unless the process runs as root since only root can bind port addresses 035 * lower than 1024. 036 * <p> 037 * Example: java rshell myhost localusername remoteusername "ps -aux" 038 * <p> 039 * Usage: rshell <hostname> <localuser> <remoteuser> <command> 040 * <p> 041 ***/ 042 043 // This class requires the IOUtil support class! 044 public final class rshell 045 { 046 047 public static final void main(String[] args) 048 { 049 String server, localuser, remoteuser, command; 050 RCommandClient client; 051 052 if (args.length != 4) 053 { 054 System.err.println( 055 "Usage: rshell <hostname> <localuser> <remoteuser> <command>"); 056 System.exit(1); 057 return ; // so compiler can do proper flow control analysis 058 } 059 060 client = new RCommandClient(); 061 062 server = args[0]; 063 localuser = args[1]; 064 remoteuser = args[2]; 065 command = args[3]; 066 067 try 068 { 069 client.connect(server); 070 } 071 catch (IOException e) 072 { 073 System.err.println("Could not connect to server."); 074 e.printStackTrace(); 075 System.exit(1); 076 } 077 078 try 079 { 080 client.rcommand(localuser, remoteuser, command); 081 } 082 catch (IOException e) 083 { 084 try 085 { 086 client.disconnect(); 087 } 088 catch (IOException f) 089 {} 090 e.printStackTrace(); 091 System.err.println("Could not execute command."); 092 System.exit(1); 093 } 094 095 096 IOUtil.readWrite(client.getInputStream(), client.getOutputStream(), 097 System.in, System.out); 098 099 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