Daisuke Murase


Cocoa::BatteryInfo - Getting battery informations on your Mac


Get battery informations

    use Cocoa::BatteryInfo;
    # get information for first battery source
    my $info = Cocoa::BatteryInfo->current_info;
    # get information for all battery sources
    my @sources = Cocoa::BatteryInfo->sources;
    for my $source (@sources) {
        my $info = Cocoa::BatteryInfo->current_info($source);
    # get estimated time remaining until all power sources are empty
    my $sec = Cocoa::BatteryInfo->time_remaining_estimate;

Get battery related notifications with Cocoa::EventLoop

    use Cocoa::BatteryInfo;
    use Cocoa::EventLoop;
    Cocoa::BatteryInfo::low_battery_handler {
        # called when the battery time remaining drops into a warnable level.
        my $warning_level = Cocoa::BatteryInfo->battery_warning_level;
    Cocoa::BatteryInfo::time_remaining_handler {
        # called when the power source(s) time remaining changes.
        my $remaining_sec = Cocoa::BatteryInfo->time_remaining_estimate;
    # run event loop


This module provides several functions to get battery information about your Mac computers. Optionally this module also supports some notifications (low battery notifications, time remaining change notifications) with Cocoa::EventLoop.

This module requires Mac OS X 10.7 or later because it depends new IOKit APIs.


info($source_name : Str)

    my $info = Cocoa::BatteryInfo->info;
    # or
    my $info = Cocoa::BatteryInfo->info($source_name);

Returns readable information about the specific power source.

If $source_name is not set, returns first source information. If system doesn't have any battery, returns nothing.


    my @sources = Cocoa::BatteryInfo->sources;

Returns list of power sources that connected to current machine.


    my $sec = Cocoa::BatteryInfo->time_remaining_estimate;

Returns 'unknown' if the OS cannot determine the time remaining. Returns 'unlimited' if the system has an unlimited power source.

Otherwise returns estimated time remaining until all power sources are empty (in seconds).


    my $level = Cocoa::BatteryInfo->battery_warning_level;

Indicates whether the system is at a low battery warning level.

$level is one of following levels:

  • Cocoa::BatteryInfo::LowBatteryWarningNone (== 1) (No battery warnings)

  • Cocoa::BatteryInfo::LowBatteryWarningEarly (== 2) (Early battery warnings)

  • Cocoa::BatteryInfo::LowBatteryWarningFinal (== 3) (Final battery warnings)


low_battery_handler($callback :CodeRef)

Register low battery event handler called when the battery time remaining drops into a warnable level.

time_remaining_handler($callback :CodeRef)

Register time remaining event handler called when the power source(s) time remaining changes.


Callbacks listed above do nothing without under the Cocoa's event loop.

To work those callbacks correctly, you have to use this module with Cocoa::EventLoop:

    use Cocoa::EventLoop;
    use Cocoa::BatteryInfo;
    Cocoa::BatteryInfo::low_battery_handler {
        # do something;


Daisuke Murase <typester@cpan.org>


Copyright (c) 2012 Daisuke Murase. All rights reserved.

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

The full text of the license can be found in the LICENSE file included with this module.