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4. Linux Scheduling Tools and vSchedule

Linux has almost any implementation you might want of the Unix "cal" program. (I'm aware of at least 4.) "cal" is perhaps best known for the somewhat unusual looking results you get if you type: cal 9 1752

There are variants such as gcal (the FSF version) that provide more sophistication, but essentially these are all just different ways to display a calendar, providing no ability to associate events with the calendars.

Then there's the shell-based "Unix scheduler" programs:

(in roughly increasing order of sophistication/power/frequency of upgrades)

Then there's the X-based tools, notably:

These programs have varying degrees of interoperability with other systems. One that I particularly have reason to care about is integration with my 3COM Pilot. It's worth noting that there do exist tools to export Pilot's "Date Book" scheduling information in formats compatible with remind and Ical. (See the pilot-link package included in most Linux distributions for more details. There is also

There is an (Internet Engineering Task Force) committee responsible for a standard format for managing scheduling information that is known as iCalendar. This was originally developed by an organization called Versit; it has since become an official IETF committee, with information findable at: IETF Calendaring and Scheduling Committee

A further effort has created an XML DTD providing a different "syntax" for representing iCal information; Representing vCard Objects in RDF/XML .

There are now a number of products that support iCalendar, notably including:

A whole *pile* of vendors are on board to make use of the format, including (just to mention a very few):


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