$ cat abc.pl
print "hello world\n";
print "goodbye world\n";

##</code><code>##

$ cd
$ perl ~/learn/perl/p5p/abc.pl
hello world
goodbye world

##</code><code>##

$ perl -d ~/learn/perl/p5p/abc.pl

Loading DB routines from perl5db.pl version 1.49_04
Editor support available.

Enter h or 'h h' for help, or 'man perldebug' for more help.

main::(/home/jkeenan/learn/perl/p5p/abc.pl:1):
1:	print "hello world\n";
  DB<1> c
hello world
goodbye world
Debugged program terminated.  Use q to quit or R to restart,
use o inhibit_exit to avoid stopping after program termination,
h q, h R or h o to get additional info.
  DB<1> q

##</code><code>##

$ cd learn/perl/p5p
$ perl -d abc.pl
hello world
goodbye world
Var=

##</code><code>##

$ cd xyz
$ perl -d ../abc.pl

Loading DB routines from perl5db.pl version 1.49_04
Editor support available.

Enter h or 'h h' for help, or 'man perldebug' for more help.

main::(../abc.pl:1):	print "hello world\n";
  DB<1> c
hello world
goodbye world
Debugged program terminated.  Use q to quit or R to restart,
use o inhibit_exit to avoid stopping after program termination,
h q, h R or h o to get additional info.
  DB<1> q

##</code><code>##

$ echo $PERLDB_OPTS