in reply to waitpid and Windows

... but doesn't perform as expected in the Windows world.

That's a pretty poor description of the problem. What are you expecting and how does what you are seeing differ from that?

The non-blocking form of waitpid seems to work fine on my system: 

use POSIX qw[ :sys_wait_h ];;
$pid = open O, '| perl.exe -e"sleep 10; exit(123)"' or die $!;;
print waitpid( $pid, &WNOHANG ) while sleep 1;;
0
0
0
0
0
0
0
4360
-1
-1
-1
Terminating on signal SIGINT(2)

[download]

So how is it "not performing as expected" for you?

Also, showing the open being used woudl be a good idea as that can influence things.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

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Re^2: waitpid and Windows
by jeffthewookiee (Sexton) on Jun 02, 2007 at 11:59 UTC
    It seems to hang on the waitpid() call instead of returning immediately and moving on to the next loop step.
[reply]
      It seems to hang on the waitpid()

      It's not hanging - you're just not seeing the output.

      To see the output you'll need to run BrowserUK's code as perl -l script.pl. Alternatively, you could change the third line of the code to: 
      print waitpid( $pid, &WNOHANG ), "\n" while sleep 1;;

      [download]
      Cheers,
      Rob
[reply]
[d/l]
[select]

      Did you try running the snippet I posted above?

      Here it is as a one-liner in case you couldn't see how to run it. (You'll need to enter it as a single line.) 

      C:\test>perl -MPOSIX=:sys_wait_h 
-le"$pid=open O, q[perl -esleep(10)|];print waitpid $pid,&WNOHANG whil
+e sleep 1"
0
0
0
0
0
0
0
0
0
3204
-1
-1
Terminating on signal SIGINT(2)

      [download]

      You'll need ^C to terminate it. What results did you see?

      If you can eliminate your installation and platform as a source of the problem, then you might look more closely at your implementation. Maybe post a bit more code? Including the open as I requested?

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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