1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.term; 18 19 import java.io.FileDescriptor; 20 21 /** 22 * Utility methods for creating and managing a subprocess. 23 * <p> 24 * Note: The native methods access a package-private 25 * java.io.FileDescriptor field to get and set the raw Linux 26 * file descriptor. This might break if the implementation of 27 * java.io.FileDescriptor is changed. 28 */ 29 30 public class Exec 31 { 32 static { 33 System.loadLibrary("term"); 34 } 35 36 /** 37 * Create a subprocess. Differs from java.lang.ProcessBuilder in 38 * that a pty is used to communicate with the subprocess. 39 * <p> 40 * Callers are responsible for calling Exec.close() on the returned 41 * file descriptor. 42 * 43 * @param cmd The command to execute 44 * @param arg0 The first argument to the command, may be null 45 * @param arg1 the second argument to the command, may be null 46 * @param processId A one-element array to which the process ID of the 47 * started process will be written. 48 * @return the file descriptor of the started process. 49 * 50 */ 51 public static native FileDescriptor createSubprocess( 52 String cmd, String arg0, String arg1, int[] processId); 53 54 /** 55 * Set the widow size for a given pty. Allows programs 56 * connected to the pty learn how large their screen is. 57 */ 58 public static native void setPtyWindowSize(FileDescriptor fd, 59 int row, int col, int xpixel, int ypixel); 60 61 /** 62 * Causes the calling thread to wait for the process associated with the 63 * receiver to finish executing. 64 * 65 * @return The exit value of the Process being waited on 66 * 67 */ 68 public static native int waitFor(int processId); 69 70 /** 71 * Close a given file descriptor. 72 */ 73 public static native void close(FileDescriptor fd); 74 } 75 76