in reply to Re^8: Please suggest a non-forking way to do this (OS: windows)
in thread Please suggest a non-forking way to do this (OS: windows)

Not quite. 

use strict;
use warnings;

use Fcntl qw( F_SETFL O_NONBLOCK );

my $fh = \*STDIN;
fcntl($fh, F_SETFL, O_NONBLOCK) || die "$!\n"; 
sysread($fh, my $buf, 1);

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Your vendor has not defined Fcntl macro F_SETFL, used at ...

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Similarly, $fh->blocking(0); is a no-op.

Like I said earlier, as far as I know, it's impossible to detect whether the pipe has data waiting.

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Re^10: Please suggest a non-forking way to do this (OS: windows)
by BrowserUk (Patriarch) on Sep 30, 2008 at 15:19 UTC
    as far as I know, it's impossible to detect whether the pipe has data waiting.

    Actually, you can. See PeekNamedPipe() which is explicitly documented as also working on:

    a handle to the read end of an anonymous pipe, as returned by the CreatePipe function.

    Though it is difficult to see how to integrate it with win32/win32sck.c win32_select() in order to allow select to operate in the *nix fashion on pipes as well as sockets?

    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.
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[d/l]

      Win32API::File has a function that returns the system file handle associated with a Perl file handle, and Win32::API can give access to PeekNamedPipe with minimal fuss.

      Sounds like it's another working solution in this case, even if it can't be integrated with select.

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[d/l]
[select]
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Re^10: Please suggest a non-forking way to do this (OS: windows)
by zentara (Cardinal) on Sep 30, 2008 at 14:35 UTC
    Not quite

    Are you saying the non-blocking script I posted didn't work for you? This slightly modified version using STDIN works fine, in a non-blocking manner for me on linux. Is your error coming on a Windows platform? If thats so, nothing I can do, except encourage people to switch to a real operating system, instead of a game platform. :-)

    Read more... (1494 Bytes)

    s far as I know, it's impossible to detect whether the pipe has data waiting.

    On linux you can, see "perldoc -q waiting".

    I'm not really a human, but I play one on earth Remember How Lucky You Are
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[d/l]

      This slightly modified version using STDIN works fine, in a non-blocking manner for me on linux.

      I just showed that your fcntl command doesn't work on Windows.

      Is your error coming on a Windows platform? If thats so, nothing I can do, except encourage people to switch to a real operating system, instead of a game platform. :-)

      Windows does have an equivalent to unix's file handles and select (events that can be tied to file handles and WaitForMultipleObjects), but Perl doesn't support them.

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[d/l]
[select]
        For the sake of the original poster, would you know the names of the Win32 modules that implements the select function, and/or anything that relates to reading pipes?
        I'm not really a human, but I play one on earth Remember How Lucky You Are
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