1 /*
   2  * Copyright (c) 2006, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 6474073
  27  * @summary Make sure zombies don't get created on Unix
  28  * @author Martin Buchholz
  29  */
  30 
  31 import java.io.*;
  32 
  33 public class Zombies {
  34 
  35     static final String os = System.getProperty("os.name");
  36 
  37     static final String TrueCommand = os.contains("OS X")?
  38         "/usr/bin/true" : "/bin/true";
  39 
  40     public static void main(String[] args) throws Throwable {
  41         if (! new File("/usr/bin/perl").canExecute() ||
  42             ! new File("/bin/ps").canExecute())
  43             return;
  44         System.out.println("Looks like a Unix system.");
  45         final Runtime rt = Runtime.getRuntime();
  46 
  47         try {
  48             rt.exec("no-such-file");
  49             throw new Error("expected IOException not thrown");
  50         } catch (IOException _) {/* OK */}
  51 
  52         try {
  53             rt.exec(".");
  54             throw new Error("expected IOException not thrown");
  55         } catch (IOException _) {/* OK */}
  56 
  57         try {
  58             rt.exec(TrueCommand, null, new File("no-such-dir"));
  59             throw new Error("expected IOException not thrown");
  60         } catch (IOException _) {/* OK */}
  61 
  62         rt.exec(TrueCommand).waitFor();
  63 
  64         // Count all the zombies that are children of this Java process
  65         final String[] zombieCounter = {
  66             "/usr/bin/perl", "-e",
  67             "exit @{[`/bin/ps -eo ppid,s` =~ /^ *@{[getppid]} +Z$/mog]}"
  68         };
  69 
  70         int zombies = rt.exec(zombieCounter).waitFor();
  71         if (zombies != 0) throw new Error(zombies + " zombies!");
  72     }
  73 }