Windows was not designed with forking in mind. I get the same problem using backticks - they work fine in the parent but hang in the child. Probably relates to the fork() implementation/emulation on Windows. Solution - don't use backtics in child. This works fine using the Net::Ping module.

use Net::Ping;

pipe (FROM_CHILD, TO_PARENT) or die "Oops Pipe: $!\n";
pipe (FROM_PARENT, TO_CHILD) or die "Oops Pipe: $!\n";
select((select(TO_CHILD),  $|++ )[0]); # set autoflush
select((select(TO_PARENT), $|++ )[0]); # set autoflush
$|++;
my $result;

# let's fork
if ( my $pid = fork ) {
    # this is parent
    print "Sending to kid\n";
    sleep 1;
    print TO_CHILD "perlmonks.org\n";  
    chomp( my $child_says = <FROM_CHILD> );
    print "Child says '$child_says' to parent\n";
    $result = $child_says;
    waitpid( $pid, 0 );
} else {
    # this is child
    die "Can't fork: $!\n" unless defined $pid;
    print "Waiting to get info from parent\n";
    chomp( my $parent_says = <FROM_PARENT> );
    print "Parent says '$parent_says' to child\n";
    my $p = Net::Ping->new();
    my $ping = $p->ping($parent_says);
    print "Net::Ping in child returned: $ping\n";
    $p->close();
    print TO_PARENT "Child pid $$ replies:$ping\n";
    exit;
}


close FROM_CHILD; close TO_CHILD;
close FROM_PARENT; close TO_PARENT;

print "Parent got $result\n";
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

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