FTA: I’d be really excited to hear all the use cases for gcal one can come up with. Seems really suited for a TODO list manager or to never forget a birthday again.
$ man calendar
CALENDAR(1) General Commands Manual CALENDAR(1)
NAME
calendar - reminder service
SYNOPSIS
calendar [-abw] [-A num] [-B num] [-f calendarfile] [-t [[[cc]yy]mm]dd]
DESCRIPTION
The calendar utility checks the current directory or the directory
specified by the CALENDAR_DIR environment variable for a file named
calendar and displays lines that begin with either today's date or
tomorrow's. On Fridays, events on Friday through Monday are displayed.
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