$\="\n";
sub show {
    print join "\t",(caller(0))[0..3];
};

show();

*func = \&show;

func();

##</code><code>##

/usr/bin/perl -w /tmp/tst.pl 
main	/tmp/tst.pl	6	main::show
main	/tmp/tst.pl	10	main::show