Invoking Perl debugger so that it runs until first breakpoint - perl

Question

When I invoke my Perl debugger with perl -d myscript.pl, the debugger starts, but it does not execute any code until I press n (next) or c (continue).
Is there anyway to invoke the debugger and have it run through the code by default until it hits a breakpoint?
If so, is there any statement that I can use in my code as a breakpoint to have the debugger stop when it hits it?
Update:
Here is what I have in my .perldb file:
print "Reading ~/.perldb options.\n";
push #DB::typeahead, "c";
parse_options("NonStop=1");
Here is my hello_world.pl file:
use strict;
use warnings;
print "Hello world.\n";
$DB::single=1;
print "How are you?";
Here is the debugging session from running: perl -d hello_world.pl:
Reading ~/.perldb options.
Hello world
main::(hello_world.pl:6): print "How are you?";
auto(-1) DB<1> c
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> v
9563 9564
9565 sub at_exit {
9566==> "Debugged program terminated. Use `q' to quit or `R' to restart.";
9567 }
9568
9569 package DB; # Do not trace this 1; below!
DB<1>
In other words, my debugger skips print "How are you?", and instead stops once the program finishes, which is not what I want.
What I want is have the debugger run my code without stopping anywhere (nor at the beginning, nor at the end of my script), unless I explicitly have a $DB::single=1; statement, in which case I would like it to stop before running the next line. Any ways to do this?
For reference, I am using:
$perl --version
This is perl 5, version 14, subversion 1 (v5.14.1) built for x86_64-linux

Answer 1

Put
$DB::single = 1;
before any statement to set a permanent breakpoint in your code.
This works with compile-time code, too, and may be the only good way to set a breakpoint during the compile phase.
To have the debugger automatically start your code, you can manipulate the #DB::typeahead array in either a .perldb file or in a compile-time (BEGIN) block in your code. For example:
# .perldb file
push #DB::typeahead, "c";
or
BEGIN { push #DB::typeahead, "p 'Hello!'", "c" }
...
$DB::single = 1;
$x = want_to_stop_here();
There is also a "NonStop" option that you could set in .perldb or in the PERLDB_OPTS environment variable:
PERLDB_OPTS=NonStop perl -d myprogram.pl
All of this (and much more) is discussed deep in the bowels of perldebug and perl5db.pl
Update:
To address the issues raised in the most recent update. Use the following in ./perldb:
print "Reading ~/.perldb options.\n";
push #DB::typeahead, "c";
parse_options("inhibit_exit=0");

Answer 2

Also check out Enbugger. And while on the topic of debuggers, see Devel::Trepan which also works with Enbugger.