Runtime.exec using extended envp

Hello,
I would like to call Runtime.exec(String[], String[]), using the already existing environment variables with some modifications. Anyone have a tip how to accomplish this?

ugly hack, yes but it should work:
in pseudocode:
Process p = Runtime.exec(my Shell's name);
p.getOutputStream().write("setenv stuff"); // do this to modify your enviornment
p.getOutputStream().write("my executable");
That would allow you to modify the enviornment of your child process.

Similar Messages

  • Runtime.exec() paramater "String[] envp"

    Hi,
    envp - array of strings, each element of which has environment variable settings in the format name=value, or null if the subprocess should inherit the environment of the current process.
    That's a formal definition of Runtime.exec()'s function argument
    but what exactly it is responsible for?
    Could you give me any usage examples?
    Thanks!

    It's responsible for setting the environment variable.
    String[] envvars = { "temp=C:\TEMP" };

  • Runtime.exec() - using cp and files with spaces on unix

    I'm using the Runtime.exec method to copy files in a unix environment. This works fine until there is a file where the name has spaces in it. I've read the article on the pitfalls of using runtime and how it breaks a string on white spaces and this is what is happening. I've also found another topic that was having the same problem, but they were using /usr/bin/dos2unix. I've tried putting quotes around the filename, but it still breaks on the first space. Any suggestions on how to get around this or another way of doing this would be greatly appreciated.
    An example of the os command string is:
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    Thanks!

    Hi!
    Well I dont have any Sun machine right here to try this but in windows It works great.
    Have you tried something like this ?
    import java.io.*;
    public class OSCopy {
        public static void main(String[] args) {
            try {
                String space = " ";
                String copycmd = "E:\\cp.cmd";
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                Process copy = runtime.exec( cmd );
                BufferedReader reader = new BufferedReader( new InputStreamReader( copy.getInputStream()) );
                String line = null;
                while( (line = reader.readLine()) != null ) {
                    System.out.println( line );
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    cp.cmd is a simple dos copy command
    copy %1 %2
    */good luck!

  • Trying to run external script using Runtime.exec

    Hey,
    I am trying to use Runtime.exec(cmd, evnp, dir) to execute a fortran program and get back its output, however it seems to always be hanging. Here is my code snippet :
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                      "./fortranCodeName > inputFile.txt" , null, new File("/home/myRunDir/"));
                InputStream stream = new InputStream(process.getInputStream());
                InputStream error = new InputStreamr(process.getErrorStream());
                BufferedReader stdoutReader = new BufferedReader(new InputStreamReader(stream));
                BufferedReader erroutReader = new BufferedReader(new InputStreamReader(error));
                System.out.println(stream.available());  //returns 0
                System.out.println(error.available());     //returns 0
                while (true) {
                    String line1 = stdoutReader.readLine();  //hangs here
                    String line2 = erroutReader.readLine();
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    Okay, so I implemented the changes from that website (thanks by the way for that link, it helps me understand this a little better). However, my problem is still occuring. Here is my new code:
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                InputStream is;
                String type;
                StreamThread(InputStream is, String type)
                    this.is = is;
                    this.type = type;
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                    try
                        InputStreamReader isr = new InputStreamReader(is); //never gets called
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                        String line=null;
                        while ( (line = br.readLine()) != null)
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                Process process = Runtime.getRuntime().exec(
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  • Issue using Runtime.exec() in Vista

    I've coded a simple method using Runtime.exec() to get the client MAC ID , and it worked alright on XP. Now my client want to switch to vista , and the method is not working. Here's my code
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    import java.util.regex.*;
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         public static String getMacAddress()
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              System.out.println("getMacAddress");
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               * @param cmd
              public RunTimeExecutor(String cmd)
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    thx guys for ur replies . The issue was because of some browser security system ( or so they said . ).However i'm still puzzled about the 'waiting for the stream to finish' part .
    paul.miner wrote:
    {I think the process is allowed to end with output still in the >>buffers, ..so this would be expected. You should be waiting for >>your .streams to finish, since that's what you really >>care .about. .Also, .you need to add synchronization between your >>threads so you can accurately retrieve "MAC". Also, do not break out >>of the loop when you find what you're looking for, you should >>continue .reading until the end of the stream.Wasn't I suppose to be reading out of the stream to prevent an overflow?Also the break is done there are multiple lines like 'Physical address .....: xxxxxxxxxx ' in the output , and the macid is the first one.About the ProcessBuilder , I'll look into it . Thx for your advice.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

  • IOException File not found - While using Runtime.exec

    Hey All,
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            at java.lang.Runtime.execInternal(Native Method)
            at java.lang.Runtime.exec(Runtime.java:566)
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    Thanks in advance for your time and efforts.

    I found the problem after extensively searing the forums (looking upto page 4 !! of the results). The problem was that I was using quotes to surround the paths in the command. If you copy and paste it in a terminal it will work fine but it does not work with runtime.exec. I am not sure, but I think the reason is that when a terminal is used, some pre-processing of the commands take place before they are passed onto the OS(shell). But while using runtime.exec, that pre-processing is not peformed and therefore some things will not work.
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  • Why couldn't I use Runtime.exec(cmd)?

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  • BufferedReader blocks when using Runtime.exec()

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    I use this type of thing in my code using JDK1.3.1. Only difference is I don't use set up the readers in threads. I suspect you have a thread deadlock, but I can't see why. Do you have to have the i/o stream readers in the thread?

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  • PATH Setting using Runtime.exec() on a UNIX env?

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