The App-orgdaemon distribution provides the "org-daemon" program, a
Perl/Tk application which sits in the background and "warns" about
appointments found in configured Emacs org-mode files.

Installation:

       perl Makefile.PL
       make
       make test
       make install

Installation without downloading the distribution:

       cpan App::orgdaemon

or

       cpanm App::orgdaemon

You can use the org-daemon script found in the bin subdirectory also
directly, without installation. Make sure that at least Perl/Tk is
installed. On a Debian based system this dependency could be installed
using

       sudo apt-get install perl-tk

Usage:

       org-daemon --recheck-interval=3 /path/to/TODO.org &

Run "perldoc bin/org-daemon" or "tkpod bin/org-daemon" for complete
documentation.