Hello!
Simply put, I'm writing a perl/tk gui, containing a text widget and a Run button. My intent is for Run to open a pipe to the output of another perl script of mine. I want to read the output and insert it into the text widget. My other perl script (test.pl) takes a while to run, so I want to make sure that I'm using non-blocking I/O and a callback for when the pipe is readable, so that my gui doesn't freeze. So far I've tried using Tk's fileevent and the Tk::IO module, both without success. (I believe the Tk::IO's exec creates a separate thread for running my other script.) Here are some snippets from my latest attempt: 
use Tk::IO;

# callback for 'Run' Button
sub RunCB {
  $fh = new Tk::IO->new(-linecommand => \&guiReadTestHandle,
                       -childcommand => \&guiCloseTestHandle);
  $fh->exec("test.pl");
}

# callback for when $fh is readable<BR>
sub guiReadTestHandle {
  if (<$fh>) {
    $txtRunRslt->insert(end, $data);
  }
}

# callback for when $fh reaches EOF
sub guiCloseTestHandle {
  $fh->close();
}

[download]
When I run the program and click 'Run', I get the message '-' is not recognized as an internal or external command, operable program or batch file., then the guiCloseTestHandle is called, closing the filehandle. I'm running on Win2K, with ActivePerl 5.6.1. The Tk::IO version appears to be 3.038. If anyone has any information on what I'm doing wrong, or how I can better achieve this, I would really appreciate it! Thanks, all.

In reply to fileevent or Tk::IO with pipes by csotzing

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