I've included the method I'm having trouble with at the end of the post.

I was using Runtime.getRuntime().exec(String) to execute programs and had no
problem with it at all, but since I had to include an argument, I was
worried about problems with spaces in program names, so I switched
to .exec(String[]) instead of .exec(String).  I figure this way when it
turns out I have to run a program with a space in the filename, there
should be no problem.

When I was specifying the program with only a String, every program I would
attempt would run.  Now that I'm using String[], I have times where I run
one program and it works, then run the same program, with the same
arguments, a few seconds later, and waitFor() returns immediately and I get
no data from the ErrorStream or InputStream.

I tried, as an experiment, to put quotation marks around the filename in a
string so it would look like this:

"/usr/bin/myprogram" -myargument

And that would not work -- the programs would not run at all.

Also as an experiment, in the spot I marked with a comment, I tried a
sleep() call, just in case waiting had any effect.  When I had it wait 100
milliseconds, every time I ran a program, I got data from the appropriate
InputStream or ErrorStream, but not all the data I should have (it was
lopped off at the beginning).  I tried shorter times for sleep() and with
10 milliseconds, no programs ran.

So why is it that sometimes the program runs and I get input and sometimes
it doesn't?  My best guess is that the program always runs, but that there
might be a timing issue that keeps me from reading the streams quickly
enough, but that doesn't sound likely.

Any help is appreciated.

Thanks!

Hal

------Code method-----
public boolean runFile()
{
       stopFlag = false;
       System.out.println("DEBUG: Starting to run file, Command: " + runLine);
       try
       {
               Process procRun = Runtime.getRuntime().exec(cmdInfo);
               iRead = new BufferedReader (new
                       InputStreamReader(procRun.getInputStream()));
               eRead = new BufferedReader (new
                       InputStreamReader(procRun.getErrorStream()));
               System.out.println("\tDEBUG: Buffers made");
//Tried to use Thread.sleep() here with different timings
//Thread to read Standard output
//Only exception thrown by BufferedReader.readLine() is EOF, which
//means we're at the end, so there's no need to do anything with it.
               new Thread(
                       new Runnable() {
                               public void run() {
                                       String sRead;
                                       try {
                                               while ((sRead = iRead.readLine()) != null) {
                                                       System.out.println("DEBUG: Standard:" + sRead);
                                                       outData = outData + sRead;
                                                       if (stopFlag)
                                                               break;                                                          
                                               }
                                       } catch (Exception eofE) {}
                               }
                       }
               ).start();
               
//Thread to read Error output
               new Thread(
                       new Runnable() {
                               public void run() {
                                       String sRead;
                                       try {
                                               while ((sRead = eRead.readLine()) != null) {
                                                       System.out.println("DEBUG: Error:" + sRead);
                                                       outError = outError + sRead;
                                                       if (stopFlag)
                                                               break;
                                               }
                                       } catch (Exception eofE) {}
                               }
                       }
               ).start();
                       
               procRun.waitFor();
               stopFlag = true;                        
               System.out.println("\tDEBUG: Run is complete");
               iStream.close();
               eStream.close();
       }
       catch (Exception e)
       {
               System.err.println("Could not execute IDFile: " + runLine);
               return false;
       }
       System.out.println("\tDEBUG: Done running file");
       return true;
}