in reply to Re: spawning Perl scripts
in thread spawning Perl scripts

True, this will work in Win32 from the command line. However, when attempting to use a fork/exec solution through an IIS server, the parent still hangs and waits for the child to finish.

The output I get is:
Fri Mar 28 12:33:52 2003: Hello from the parent (473)!
Fri Mar 28 12:33:52 2003: Hello from the child (-480)!
Fri Mar 28 12:33:52 2003: Goodbye from the parent (473)!

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However, there is a thirty second pause between the display of 'Hello from the child' and 'Goodbye from the parent.' The machine thinks the parent process is done (timestamps), but server keeps crunching until the child terminates, only then does it display whatever is past the exec in the parent.

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Re: spawning Perl scripts
by Abigail-II (Bishop) on Mar 28, 2003 at 22:20 UTC
    Reason number #2647 to not use Windows.

    Abigail

[reply]

      {grin} I could have antisipated that reaction:0

      I guess I could categorise that under the "doesn't work like unix" heading. Although, at the fundemental level, the differences between forking the current process into two processes and then immediately overlaying that process with another process using exec as a mechanism for starting an asynchronous process is a little conveluted. No more so than forking a shell and have it start the asynchronous process I would add.

      The nice thing about the Win32::Process route is that you ask the OS to start the asyncronous process for you with a single API call without the need for all the intermediate steps. I'm surprised that after all this time there is no similar create-an-asynchronous-process-running-this-command system call available under unix.

      Does anyone know how this is acheived under other OS's, VMS/s390 et. They don't all follow the fork and exec model do they?

      Examine what is said, not who speaks.
      1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
      2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible
      3) Any sufficiently advanced technology is indistinguishable from magic.
      Arthur C. Clarke.
[reply]
        Well, one can of course dismiss everything under the "doesn't work like Unix" category. However, the "it works like Unix" way is what the OP wants. The "it doesn't work like Unix" way wasn't at all useful, as the parent process is waiting for its children to finish. Or at least, appears to. It wasn't the API that was complained about. It was the behaviour.

        Abigail

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