use Env qw{PRINTER LPDEST NPRINTER NGPRINTER PATH}; 

#added the following to the original code
$ENV{'PATH'}='/usr/bin';
delete @ENV{'IFS','CDPATH','ENV','BASH_ENV'};
...

#line 127
open PRINTER, "| $self->{print_command}->{linux}->{type}"
  or Carp::croak "Can't open printer connection to $self->{print_command}->{linux}->{command};