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This is a calendar program for Linux and Unix systems that will display the contents the calendar file (and any files it includes) on the day that entries in the file should be displayed. There was once a program like this on old AT&T Unix systems years ago, but we could not find similar functionality for Linux when this was written. (It is available now, thus making the tool available from this page somewhat redundant. However, some of the features like daily_calendar make it an improvement over the older calendar tool and does not exist in current Linux sources.)

This program provided here is written in Perl, is completely free open source.

To use the calendar program, put it somewhere in your path (e.g., $HOME/bin or /usr/local/bin). In your home directory, create a directory called "calendar" and a file inside that directory with the name "calendar". This is the first file that the calendar program will read. You may have any number of other calendar files included using the "include" directive. This directive may be used inside any calendar file, regardless of whether it is the primary calendar file or a child calendar file.

This is what a calendar file might look like:

Source Code

# Calendar file
# Date  Message to deliver

# Include the other calendar files
include holidays
include birthdays
include bills

# Monthly events
*-04 What you need to do on the 4th

# Business events
06-01 Some business tax forms due by June 30
2034-05-01 Some event scheduled in the future

Lines starting with a "#" are considered comments and are ignored. Blank lines (those without any text other than spaces and tabs) are also ignored. Calendar entries have a date followed by a text string that would be shown to the user. Dates in a calendar entry may take several forms, including "mm-dd-yy", "yyyy-mm-dd", or "mm-dd". The "-" character may be replaced with the "/" character. Not all date forms used around the world can be supported, since there is no way to differentiate between them. For example, a computer cannot tell the difference between "mm/dd/yyyy" and "dd/mm/yyyy".

In the place of any month, day, or year position in the date, one may use an "*", which will always match. So, if you want a calendar entry to always match the first of the month, use a date of "*-01".

To use this program, simply put an entry into your crontab like this:

Source Code

30  3  *  *  *  $HOME/bin/calendar

You can download the latest calendar files here.