#!/usr/bin/perl

# In order to 'use' a perlmodule in a userspace library you need to add it to @INC.
# But if you do not want to use an absolute path inside the script, you need this workaround:
BEGIN{ 
        use Cwd 'abs_path';
        my $this = $0; # this script 
        $this =~ s/[^\/]+$//; # strip the filename, now we have a (relative) directory
        my $path = abs_path($this); # now we have an absolute directory 
        unshift @INC, $path; # which we add to @INC
        # chdir('/tmp'); # does seem to confuse abs_path! Uncomment to see
}


use My::Module;
My::Module::print_file_name();
My::Module::print_script_name();
My::Module::print_caller_name();



##</code><code>##

#!/usr/bin/perl

package My::Module;
use feature qw(say);

local $_SCRIPT = "";
local $_PATH = "";
BEGIN{ 
        use Cwd 'abs_path';
        $_PATH = $0; # this script 
        $_PATH =~ s/([^\/]+)$//; # strip the filename, now we have a (relative) directory
        $_SCRIPT = $1; # the stripped part is the filename
        $_PATH = abs_path($_PATH); # now we have an absolute directory 
         print "My::Module 0=$0 _PATH=$_PATH _SCRIPT=$_SCRIPT \n";
}

sub print_file_name {
    say __FILE__;
}

sub print_script_name {
    say "print_script_name: $_PATH/$_SCRIPT";
}


sub print_caller_name {
    my @D = caller();
    $D[1]= abs_path($_PATH.'/'.$D[1]) unless $D[1]=~m{^/};
    say "print_caller_name: @D";
}


1;

##</code><code>##

warn "ALERT ALERT ALERT" unless(-f "$_PATH/$_SCRIPT");