AnyEvent::OWNet - Client for 1-wire File System server


version 1.163170


  # IMPORTANT: the API is subject to change

  my $ow = AnyEvent::OWNet->new(host => '',
                                on_error => sub { warn @_ });

  # Read temperature sensor
            sub {
              my ($res) = @_;
              # ...

  # List all devices
  my $cv;
  $cv = $ow->devices(sub {
                       my $dev = shift;
                       print $dev, "\n";

  # Read the temperatures of all devices that are found
  $cv = $ow->devices(sub {
                       my $dev = shift;
                                sub {
                                  my $res = shift;
                                  my $value = $res->{data};
                                  return unless (defined $value);
                                  print $dev, ' = ', 0+$value, "\n";

  # short version of the above
  $cv = $ow->device_files(sub {
                            my ($dev, $file, $value) = @_;
                            print $dev, ' = ', 0+$value, "\n";
                          }, 'temperature');

  # read humidity as well
  $cv = $ow->device_files(sub {
                            my ($dev, $file, $value) = @_;
                            print $dev, $file, ' = ', 0+$value, "\n";
                          }, ['temperature', 'humidity']);


AnyEvent module for handling communication with an owfs 1-wire server daemon.


new( %parameter_hash )

Constructs a new AnyEvent::OWNet object. The parameter hash can contain values for the following keys:


The host IP of the running owserver daemon. Default is the IPv4 loopback address,


The TCP port of the running owserver daemon. Default is 4304.


The timeout in seconds to wait for responses from the server. Default is 5 seconds.

read($path, $sub)

Perform an OWNet read operation for the given path.

write($path, $value, $sub)

Perform an OWNet write operation of the given value to the given path.

dir($path, $sub)

Perform an OWNet dir operation for the given path. The callback will be called once with the list of directory entries in the data field which isn't consistent with the (misguided?) low-latency intent of this operation so using dirall() probably makes more sense provided the server supports it.

present($path, $sub)

Perform an OWNet present check on the given path.

dirall($path, $sub)

Perform an OWNet dirall operation on the given path.

get($path, $sub)

Perform an OWNet get operation on the given path.

dirallslash($path, $sub)

Perform an OWNet dirall operation on the given path.

getslash($path, $sub)

Perform an OWNet get operation on the given path.

all_cv( [ $condvar ] )

This method returns the AnyEvent condvar that is used to track all outstanding operations. It can also be used to set the initial value but this is only sensible when no operations are currently outstanding and is not normally necessary.

cleanup( @error )

This method is called on error or when the closing the connection to free up resources and notify any receivers of errors.

connect( [ $command, $callback|$condvar ] )

This method connects to the owserver daemon. It is called automatically when the first command is attempted.

devices( $callback, [ $path, [ $condvar ] ] )

This method identifies all devices below the given path (or '/' if the path is not given). An AnyEvent condvar may also be supplied that will be used to track begin and end of all actions carried out during the identification process. If no condvar is provided then one will be created. The condvar used is returned by this method.

The supplied callback is called for each device with the path to each device as the first argument and the condvar for the operation as the second argument. The intention of passing the callback the condvar (that if not provided is created by the initial call) is to enable the callbacks that need to make further asynchronous calls to use begin calls and end calls (in the async callback) on the condvar so that the complete operation may be tracked. See the "SYNOPSIS" for an example.

This method currently assumes that the owserver supports the getslash function and if this is not the case it will fail.

device_files( $callback, $file, [ $path, [ $condvar ] ] )

Visit each device using devices() and call the callback with the result of successful get() calls for $file relative to each device found. If $file is an array reference each array element is treated as a relative file.


This method is used to register an AnyEvent::Handle read type to read OWNet replies from an owserver daemon.


The code assumes that the owserver supports persistence and does not check the response flags to recognize when it does not.



OWFS Website:

OWFS Protocol Document:


Mark Hindess <>


This software is copyright (c) 2014 by Mark Hindess.

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