Debug::Client(3) debugger client side code for Padre, The Perl IDE.


This document describes Debug::Client version: 0.29


use Debug::Client;
my $debugger = Debug::Client->new(host => $host, port => $port);

Where $host is the host-name to be used by the script under test (SUT) to access the machine where Debug::Client runs. If they are on the same machine this should be "localhost". $port can be any port number where the Debug::Client could listen.

This is the point where the external SUT needs to be launched
 by first setting

  $ENV{PERLDB_OPTS} = "RemotePort=$host:$port"

then running

  perl -d script

Once the script under test was launched we can call the following:

  my $out = $debugger->get;
  $out = $debugger->step_in;
  $out = $debugger->step_over;
  my ($prompt, $module, $file, $row, $content) = $debugger->step_in;
  my ($module, $file, $row, $content, $return_value) = $debugger->step_out;
  my $value = $debugger->get_value('$x');
  $debugger->run();         # run till end of breakpoint or watch
  $debugger->run( 42 );     # run till line 42  (c in the debugger)
  $debugger->run( 'foo' );  # run till beginning of sub
  $debugger->execute_code( '$answer = 42' );
  $debugger->execute_code( '@name = qw(foo bar)' );
  my $value = $debugger->get_value('@name'); # $value is the dumped data?
  $debugger->execute_code( '%phone_book = (foo => 123, bar => 456)' );
  my $value = $debugger->get_value('%phone_book'); # $value is the dumped data?
  $debugger->set_breakpoint( "file", 23 ); # set breakpoint on file, line


  my $script = '';
  my @args   = ('param', 'param');
  my $perl = $^X; # the perl might be a different perl
  my $host = '';
  my $port = 24642;
  my $pid = fork();
  die if not defined $pid;
  if (not $pid) {
        local $ENV{PERLDB_OPTS} = "RemotePort=$host:$port"
        exec("$perl -d $script @args");
  require Debug::Client;
  my $debugger = Debug::Client->new(
    host => $host,
    port => $port,
  my $out = $debugger->get;
  $out = $debugger->step_in;
  # ...


This is a DEVELOPMENT Release only, you have been warned!

The primary use of this module is to provide debugger functionality for Padre 0.98 and beyond,

This module has been tested against Perl 5.18.0


The constructor can get two parameters: host and port.

  my $debugger = Debug::Client->new;
  my $debugger = Debug::Client->new(host => '', port => 24642);
Returns the content of the buffer since the last command

. (dot)

Return the internal debugger pointer to the line last executed, and print out that line.

Return the internal debugger pointer to the line last executed,
 and generate file-name and row for where are we now.
 trying to use perl5db line-info in naff way,


Then use the following as and when.


to get filename and row for ide due to changes in perl5db v1.35 see perl5156delta

v [line]

View a few lines of code around the current line.

s [expr]

Single step. Executes until the beginning of another statement, descending into subroutine calls.
 If an expression is supplied that includes function calls, it too will be single-stepped.


Expressions not supported.

 my ($prompt, $module, $file, $row, $content, $return_value) = $debugger->step_out();

Where $prompt is just a number, probably useless

$return_value will be undef if the function was called in VOID context

It will hold a scalar value if called in SCALAR context

It will hold a reference to an array if called in LIST context.

TODO: check what happens when the return value is a reference to a complex data structure or when some of the elements of the returned array are themselves references

Sends the stack trace command "T" to the remote debugger and returns it as a string if called in scalar context. Returns the prompt number and the stack trace string when called in array context.
Sends the stack trace command "t" Toggle trace mode.

Sends the stack trace command "S" [[!]pattern]
 List subroutine names [not] matching pattern.

Will run till the next breakpoint or watch or the end of the script. (Like pressing c in the debugger).

 $debugger->set_breakpoint($file, $line, $condition);

$condition is not currently used

 $debugger->remove_breakpoint( $self, $file, $line );
The data as (L) prints in the command line debugger.

 my $value = $debugger->get_value($x);

If $x is a scalar value, $value will contain that value. If it is a reference to a ARRAY or HASH then $value should be the value of that reference?

p expr

Same as print {$DB::OUT} expr in the current package. In particular, because this is just Perl's own print function, this means that nested data structures and objects are not dumped, unlike with the x command.

The DB::OUT filehandle is opened to /dev/tty, regardless of where STDOUT may be redirected to. From perldebug, but defaulted to y 0

From perldebug, but defaulted to y 0

 y [level [vars]]

Display all (or some) lexical variables (mnemonic: my variables) in the current scope or level scopes higher. You can limit the variables that you see with vars which works exactly as it does for the V and X commands. Requires that the PadWalker module be installed Output is pretty-printed in the same style as for V and the format is controlled by the same options.


which is now y=1 since perl 5.17.6,

V [pkg [vars]]

Display all (or some) variables in package (defaulting to main ) using a data pretty-printer (hashes show their keys and values so you see what's what, control characters are made printable, etc.). Make sure you don't put the type specifier (like $ ) there, just the symbol names, like this:

X [vars] Same as V currentpackage [vars]

Enter h or `h h' for help, For more help, type h cmd_letter, optional var

o booloption ...

Set each listed Boolean option to the value 1 . o anyoption? ...

Print out the value of one or more options. o option=value ...

Set the value of one or more options. If the value has internal white-space, it should be quoted. For example, you could set o pager=``less -MQeicsNfr'' to call less with those specific options. You may use either single or double quotes, but if you do, you must escape any embedded instances of same sort of quote you began with, as well as any escaping any escapes that immediately precede that quote but which are not meant to escape the quote itself. In other words, you follow single-quoting rules irrespective of the quote; eg: o option='this isn\'t bad' or o option=``She said, \''Isn't it?\"" .

For historical reasons, the =value is optional, but defaults to 1 only where it is safe to do so---that is, mostly for Boolean options. It is always better to assign a specific value using = . The option can be abbreviated, but for clarity probably should not be. Several options can be set together. See Configurable Options for a list of these.


Display all options.

Actually I think this is an internal method....

In SCALAR context will return all the buffer collected since the last command.

In LIST context will return ($prompt, $module, $file, $row, $content) Where $prompt is the what the standard debugger uses for prompt. Probably not too interesting. $file and $row describe the location of the next instructions. $content is the actual line - this is probably not too interesting as it is in the editor. $module is just the name of the module in which the current execution is.


Internal Methods

  • _get
  • _process_line
  • _prompt
  • _send
  • _send_get


If you get any issues installing, try install Term::ReadLine::Gnu first.

Warning if you use List request you may get spurious results.

When using against v1.35 list mode gives an undef response, also leading single quote now correct. Tests are skipped for list mode against v1.35 now.

Debug::Client 0.12 tests are failing, due to changes in perl debugger, when using v1.34

Debug::Client 0.13_01 skips added to failing tests.

 c [line|sub]

Continue, optionally inserting a one-time-only breakpoint at the specified line or subroutine.

 c is now ignoring options [line|sub]

and just performing c on it's own

Warning sub listen has bean deprecated

Has bean deprecated since 0.13_04 and all future version starting with v0.14

Perl::Critic Error Subroutine name is a homonym for built-in function

Use $debugger->listener instead

It will work against perl 5.17.6-7 with rindolf patch 7a0fe8d applied for watches


Kevin Dawson <[email protected]>

Gabor Szabo <[email protected]>


Breno G. de Oliveira <garu at>

Ahmad M. Zawawi <[email protected]>

Mark Gardner <[email protected]>

Wolfram Humann <[email protected]>

Adam Kennedy <[email protected]>

Alexandr Ciornii <[email protected]>


Copyright 2008-2011 Gabor Szabo

Some parts Copyright X 2011-2013 Kevin Dawson and CONTRIBUTORS as listed above.


This program is free software; you can redistribute it and/or modify it under the same terms as Perl 5 itself.


There is no warranty whatsoever. If you lose data or your hair because of this program, that's your problem.


Originally started out from the script from Pro Perl Debugging written by Richard Foley.

See Also