lanx@lanx-1005HA:~$ perl -de0

Loading DB routines from perl5db.pl version 1.33
Editor support available.

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

main::(-e:1):	0
  DB<1> h b
b        Sets breakpoint on current line)
b [line] [condition]
        Set breakpoint; line defaults to the current execution line;
        condition breaks if it evaluates to true, defaults to '1'.
b subname [condition]
        Set breakpoint at first line of subroutine.
b $var        Set breakpoint at first line of subroutine referenced by $var.
b load filename Set breakpoint on 'require'ing the given file.
b postpone subname [condition]
        Set breakpoint at first line of subroutine after 
        it is compiled.
b compile subname
        Stop after the subroutine is compiled.
  DB<2>