use IPC::Open3;

my $status;
sub status () {
   print "Status is: $status\n";
   $SIG{USR1} = \&status; 
}

$SIG{USR1} = \&status;

print "$$\n";
my @paths;
my $c = 10;
push @paths,"sleep ".$c++ for 0 .. 3;
$c = 0;
foreach $path (@paths) {
   print "loop ",++$c,"\n";
   my $pid = open3(*CMD_IN, *CMD_OUT, *CMD_ERR, $path);
   $status = $path;
   waitpid($pid, 0);
   print "after waitpid\n";
}