#!/usr/bin/perl -w
use strict;
use File::Copy;

my @DEVS = qw(/dev/fd0 /dev/fd1);
while (1) {
    my %name;
    foreach (@DEVS) {
      PROMPT:
	print "Name of diskette in device $_: ";
	my $name = <STDIN>;
	chomp $name;
	goto PROMPT if $name !~ /\S/;
	$name{$_} = $name;
    }
    my @pids;
    foreach (@DEVS) {
	my $r = fork();
	if (not defined $r) {
	    die "cannot fork: $!";
	}
	elsif ($r == 0) {
	    # Child.
	    print STDERR "$_ -> $name{$_}\n";
	    if (not copy($_, $name{$_})) {
		unlink $name{$_};
		die "cannot copy $_ to $name{$_}: $!";
	    }
	    exit(0);
	}
	else {
	    # Parent.
	    push @pids, $r;
	}
    }
    foreach (@pids) {
	my $r = waitpid($_, 0);
	if ($r eq $_) {
	    # Okay.
	}
	elsif ($r == -1) {
	    warn "strange, child process $_ seems not to exist";
	}
	elsif ($r == 0) {
	    warn "didn't expect 0 from waitpid() on this system";
	}
	else {
	    warn "strange result from waitpid($_, 0): $r";
	}
    }
    warn "strange, there were extra child processes" if wait() != -1;
}