capturing STDOUT after Win32::Process::Create()

bmc_mark has asked for the wisdom of the Perl Monks concerning the following question:

In Perl, I kick off a command line exe that sends data to
STDOUT. I want to catch all those bits:

  Win32::Process::Create (
     $ProcessObj2,
     $counters_fname,
     "$COUNTERS_NAME -interval $interval",
     1,
     NORMAL_PRIORITY_CLASS,
     "."
  ) || HandleProcess_Failure($COUNTERS_NAME);

  $ProcessObj2->Suspend();
  $ProcessObj2->Resume();
[download]

After that, I need to do an open(), open2() or open3(),
followed by the while loop to read data...I cannot get it to work.
I dont need to write to the exe, just capture stdout.
I will even let STDERR go to cmd shell.

Any help? I am hoping for the exact open command to
use...I have found lots of "stuff" but it's not workable code.

Comment on capturing STDOUT after Win32::Process::Create() Download Code

Replies are listed 'Best First'.
Re: capturing STDOUT after Win32::Process::Create() by ikegami (Patriarch) on Nov 30, 2004 at 15:17 UTC
open2 / open3 is something that can be done instead of CreateProcess. If you're not feeding anything to it using STDIN, you can simply use: `open(COUNTER, "$COUNTERS_NAME -interval $interval \|") or die("...: $!\n"); while (<COUNTER>) { ... }` [download]	[reply] [d/l]
Re^2: capturing STDOUT after Win32::Process::Create() by bmc_mark (Novice) on Nov 30, 2004 at 15:26 UTC
I was afraid of that...the problem is, I have to "Wait" after $COUNTERS_NAME executes for one minute. If I use your open command, I won't be able to execute another perl command while $COUNTERS_NAME executes... Can I set STDOUT to go to a file before calling Win32::Process::Create(), then set it back when done? Thanks so far, your comment cleared up a confusing post from a less prestigious source...	[reply]
Re^3: capturing STDOUT after Win32::Process::Create() by bart (Canon) on Nov 30, 2004 at 18:40 UTC
You can use IPC::Open2's `open2` or IPC::Open3's `open3` to get two virtually independently running processes, until they feel the need to communicate to one another. Check out Win32::GUI Chatterbox client for working sample code.	[reply]
Re^4: capturing STDOUT after Win32::Process::Create() by bmc_mark (Novice) on Dec 01, 2004 at 16:07 UTC
Re^3: capturing STDOUT after Win32::Process::Create() by ikegami (Patriarch) on Nov 30, 2004 at 18:04 UTC
If I use your open command, I won't be able to execute another perl command while $COUNTERS_NAME executes... Not true, you can. I have to "Wait" after $COUNTERS_NAME executes for one minute. You can use `sleep(60)`, or poll `time`, ... Can I set STDOUT to go to a file before calling Win32::Process::Create(), then set it back when done? I think you could execute `cmd /c mycommand args > outputfile` instead of just `mycommand args`	[reply] [d/l] [select]