Some OSen will allow you to assign to $0; if yours is one of them then you could use that. Otherwise your best bet might be using symlinks to the real file, or consider adding a dummy argument that's ignored that you use to differentiate between instances.

Is there any way to assign different command options/arguments for each symlinc?

I've used a symlinking approach allowing the real script to see how it was called, using a dispatch table.. perhaps this will work for your purposes:

Create a script for example /usr/sbin/myscript.pl

#!/usr/bin/perl

use strict;
use warnings;

my $ME = $0 ;
$ME =~ s@^\.\/|\/.*\/@@g;
$ME =~ /myscript.pl/ and die ("\n Please dont call me directly!\n\n");

my %workerscripts = ( 'worker01'  => \&worker01,
                      'worker02'  => \&worker02,
                      'worker03'  => \&worker03
                    );

my $real_command  = $workerscripts{&findME};
&$real_command;



#---
sub findME
{
   while ( my($k,$v) =  each %workerscripts )
   {
      return $k if $k =~ /$ME/ ;
   };
};

sub worker01
{ print "worker01 was called\n"; exit 0; };

sub worker02
{ print "worker02 was called\n"; exit 0; };

sub worker03
{ print "worker03 was called\n"; exit 0; };
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Then create links to that script:

cd /usr/bin/
ln -s /usr/sbin/myscript.pl worker01
ln -s /usr/sbin/myscript.pl worker02
ln -s /usr/sbin/myscript.pl worker03
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Invoke /usr/bin/worker01, worker02, or worker03 and the proper subroutine should be called..

Does that get you closer?
-Harold

Well, you can check the value of $0 and do different things with it. But probably the best solution is to use different parameters to ps. For instance, ps -fe will give you the parameters passed to each instance, which is probably a pretty good way of distinguishing your processes.