Message-ID: <49E864F3.1070803@romandie.com>
Date: Fri, 17 Apr 2009 13:16:03 +0200
From: Philipp <kitschen AT romandie DOT com>
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To: cygwin AT cygwin DOT com
Subject: Accessing fifo pipes from windows programs
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Hello,
I have some problems accessing a fifo file from my Java program. Fifos 
work correctly with cygwin tools, example:

  $ mkfifo fifo
  $ echo 'hello' >> fifo
This blocks. In another shell, I do:
  $ cat fifo
  hello
So this works fine. It unblocks the echo and writes the "hello".

Now trying the same thing with my java app:
  $ mkfifo fifo
  $ ls -l
  total 1
  prw-rw-rw- 1 Phil Aucun 0 Apr 17 12:58 fifo

Starting the producer (code at end of post):
  $ java -cp .. DateWriter fifo
  Fri Apr 17 13:02:20 CEST 2009
  Fri Apr 17 13:02:21 CEST 2009
  [...]
It does not block but writes into a second file instead
  $ ls -l
  total 2
  -rwxr-xr-x 1 Phil Aucun 120 Apr 17 13:02 fifo
  -rwxr-xr-x 1 Phil Aucun 120 Apr 17 13:02 fifo
Two files with the same name... The last-modif date of the original fifo 
is modified, but the content is in the first. When viewed with Windows 
explorer, one is a shortcut (with comment :\0:fc:11b6) and the other a 
pure text file.

How can I access the named pipe correctly from my Java program? 
Correctly means, that writing in the Java blocks while nobody is listening.
Thanks for your answers.
Phil

Full Java code of producer:

import java.io.File;
import java.io.FileWriter;
import java.util.Date;
public class DateWriter {
    public static void main(String[] args) throws Exception{
        File fifo = new File(args[0]);
        FileWriter writer = new FileWriter(fifo);
        while(true){
            String toWrite = new Date() + "\n";
            System.out.print(toWrite);
            writer.write(toWrite);
            writer.flush();
            Thread.sleep(1000);
        }
    }
}


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