use strict;
use warnings;

&a;
sub a{ print "a"; &b }
sub b{ print "b"; &c }
sub c{ print "c"; die "arrgh at\n" . cstack() }
sub cstack
{
    my $i=1;
    my $stack="";
    while ( my $s = (caller($i))[3] )
    {
        $stack .= "$s\n" ;
        $i++;
    }
    return $stack;
}