in reply to Problem with Windows Console input

Hello anshulzunke, and welcome to the Monastery!

It seems that when the Win32::Console object $StdIn is destroyed, it closes the STDIN filehandle. The solution would be to re-open STDIN in some way. Unfortunately, I don’t know how to do this.

A possible workaround is to keep $StdIn in existence. For example:

...
use feature 'state';
...
sub readPasswordWindows {
    ...
    state $StdIn = Win32::Console->new(STD_INPUT_HANDLE);
    ...

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This is a kludge, but it does keep STDIN open and so remove the error, allowing the script to run as intended.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

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Re^2: Problem with Windows Console input
by Anonymous Monk on Feb 24, 2014 at 05:35 UTC
    Thanks buddy it works. But yes there should be a way to re open the stdin handle.
[reply]
      But yes there should be a way to re open the stdin handle.

      There is: 

      #! perl -slw
use strict;

close STDIN;

readline(STDIN);

open *STDIN, '<', 'CON:' or die $!;

my $x = readline(STDIN);

print "Got: $x from reopened STDIN";

__END__
C:\test>junk84.pl
readline() on closed filehandle STDIN at C:\test\junk84.pl line 6.
fred
Got: fred
 from reopened STDIN

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[reply]
[d/l]

        Thanks for this! It certainly works as shown. Is it documented anywhere? I haven’t been able to find CON: in either the Perl documentation or Programming Perl. In any case, it seems I was wrong: re-opening STDIN doesn’t solve anshulzunke’s problem:

        1. If I add open *STDIN, '<', 'CON:' or die $!; immediately before the final call to readInput(), the script dies with:

          Bad file descriptor at...

        2. If I add it immediately before return $Password; in sub readPasswordWindows, there is no error but the script generates:

           Use of uninitialized value $ip in concatenation (.) or string at...

          as in the OP.

        Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

[reply]
[d/l]
[select]
        Thanks for the way for reopening the stdin :)
[reply]

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