Documentation is a bit rough

I've annotated a short test script that was kicking around in my test directory. Maybe it'll clarify things a little?

#! perl -slw
use strict;
use Win32::Socketpair qw[ winopen2_5 ];

## Open a pipe to perl.exe -c
## Retrieving the pid and the socket handle
my( $pid, $sock ) = winopen2_5( 'perl.exe', '-c' );

## Print a short script to it for syntax checking
print $sock <<'EOP';
my $x = 365.25**3;
my $y = qx[ perl -c -e"say 'boo'"; ];
my $z = sub {
    print $sock <<;
    my $x = 365.25**3;
    my $y = qx[ perl -c -e"say 'boo'"; ];
    my $z = sub {
        print $sock <<;
        my $x = 365.25**3;
        my $y = qx[ perl -c -e"say 'boo'"; ];
        my $z = sub {
            1;
        };
    };
};
EOP

## Tell the socket that we have finsihed writing to it
## Has the effect of allowing the pelr process to know 
## that no more data is coming, so it can process the script
shutdown $sock, 1;

## Read back all the output from the perl process 
## -- stdout & stderr -- and display on terminal
print while <$sock>;

## Close the socket
close $sock;

## Start another copy of perl with a one liner argument
## that outputs to both stdout and stderr
( $pid, $sock ) = winopen2_5( 'perl.exe', q[-E"say 'hello'; warn; die;
+"] );

## Tell the socket we've finished writing
shutdown $sock, 1;

## print teh retrieved output to the terminal
print while <$sock>;

## and done
close $sock;

## The output produced is below
__END__
C:\test>winopen2_5
- syntax OK

Warning: something's wrong at -e line 1.

Died at -e line 1.

hello
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