#!perl -slw
use strict;
$|++;

if( my $pid = fork ) {
	print 'Hello from ithread 1';
	sleep 5;
	open STDOUT, '>', 'fork_test.txt' or die $!;
	print STDERR 'STDOUT opened to file';
	waitpid($pid,0);
}
else {
	die 'Couldn\'t fork!' unless defined $pid;
	for( 1..10 ) {
		sleep 1;
		print 'Hello from ithread 2';
	}
}

__END__
P:\>perl58 270224.pl8
Hello from ithread 1
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
STDOUT opened to file

P:\>perl5.6.1 270224.pl8
Hello from ithread 1
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
STDOUT opened to file
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2
Hello from ithread 2