use strict;
use IPC::Open3;
use IO::Select;
use Carp;

my $cmd = "ls -al";
my $pid = open3( *cmdIn, *cmdOut, *cmdErr, $cmd) or die "can not open $cmd $!";
print "\$pid $pid"; print "\n";
$SIG{CHLD} = sub {

  print "result: Status $? in $pid\n" if waitpid($pid, 0) >0
    
};

my $select = IO::Select->new(*cmdErr, *cmdOut);
print cmdIn "\n\n$cmd\n";
close(cmdIn); 
my $input; 
while ( my @ready = $select->can_read()) { 
    foreach my $fh ( @ready ) { 
	if (fileno($fh) == fileno(cmdErr)) { 
	  	    process_errors(); 
	
	} else { 
		    print "STDOUT: ", <$fh>;
    	}
	$select->remove($fh) if eof($fh);
    } 

} #
close (cmdOut);
close(cmdErr);

sub process_errors { 
    my $select= IO::Select->new( *cmdErr ); 
    my $input; 
        while ( $select->can_read(0.1) ) { 
		sysread *cmdErr, (my $line), 1024; 
	
	last unless $line; 

	$input.= $line;
	
    } 
        croak "THERE: $input $cmd code" if $input =~ /error:/; 
        carp "HERE: $input $cmd code" if $input;
    

} 

{ 

    local $SIG {__WARN__} = 

    sub { 

	my $warning = shift ; # warning handler 

    }; # commands 

}