Name: dbT83986			Date: 02/09/99


When a process (a.exe) is executed, if the process
writes more than 488 bytes of data on it's STDOUT
and we then call the waitFor( ) method of the Process
class to wait for completion of a.exe , both 
the processes hangs.  Strange enough , if in Java
we don't wait for process completion , (mask 
call to waitFor( ) method), then the execution is 
succeeded.  Or if, in a.exe, we only write 488
bytes or less then the waitFor() method works without
hanging .


To reproduce the problem 

Step 1:

Compile the follwing file a.c into a binary a.exe :
//////
#include<stdio.h>

main()
{
        char buf[500];

/*
        // Works
        memset(buf,'\0',500);
        memset(buf,'p',488);
        fprintf(stdout,"%s",buf);
*/
        // dosen't Works
        memset(buf,'\0',500);
        memset(buf,'p',489);
        fprintf(stdout,"%s",buf);
}

/////////////

Step 2:

Compile the following Java program (within a directory test) execute it.
///////////
package test;

import java.io.*;
import java.lang.*;

/**
 * Class for testing
 */
public class Test {
    public static void main(String[]args) {
	InputStream input;
	BufferedReader buf;
	String str;
	Process process;
	Runtime runtimeContext;
	try {
		runtimeContext = Runtime.getRuntime();
		process = runtimeContext.exec("a");
		process.waitFor();
		input = process.getInputStream();
		buf = new BufferedReader(new InputStreamReader(input));
		while((str = buf.readLine()) != null) {

			System.out.println(str);
		}
	
	}
	catch(IOException e) {}
	catch(InterruptedException e) {};
    }
}

/////////////////////////

Step 3:

Run java test.Test to execute Java program and exec
a.exe through JVM.
(Review ID: 40393)
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