/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.shadowsocks;
import java.io.FileDescriptor;
/**
* Utility methods for creating and managing a subprocess.
* <p>
* Note: The native methods access a package-private java.io.FileDescriptor
* field to get and set the raw Linux file descriptor. This might break if the
* implementation of java.io.FileDescriptor is changed.
*/
public class Exec {
static {
System.loadLibrary("exec");
}
/**
* Close a given file descriptor.
*/
public static native void close(FileDescriptor fd);
/**
* Create a subprocess. Differs from java.lang.ProcessBuilder in that a pty
* is used to communicate with the subprocess.
* <p>
* Callers are responsible for calling Exec.close() on the returned file
* descriptor.
*
* @param cmd
* The command to execute
* @param args
* An array of arguments to the command
* @param envVars
* An array of strings of the form "VAR=value" to be added to the
* environment of the process
* @param processId
* A one-element array to which the process ID of the started
* process will be written.
* @return the file descriptor of the started process.
*
*/
public static native FileDescriptor createSubprocess(String cmd,
String[] args, String[] envVars, int[] processId);
/**
* Send SIGHUP to a process group.
*/
public static native void hangupProcessGroup(int processId);
/**
* Causes the calling thread to wait for the process associated with the
* receiver to finish executing.
*
* @return The exit value of the Process being waited on
*
*/
public static native int waitFor(int processId);
}