To send a one-line reminder, I use a one-line command like this:
at 0427 tuesdayat>
echo "send summary to Tim today" | mail email@example.com> [CTRL-d] %
It sends mail at (in this case) 4:27 a.m. on the next Tuesday. The mail says: "send summary to Tim today."
To send more than one line, you can use a temporary file:
vi msgfile...put message body in msgfile... %
at 0808 feb 28at>
mail firstname.lastname@example.org < msgfileat>
rm msgfileat> [CTRL-d] %
Combine the output of UNIX commands and text withand a :
mail -s "Hard-working people" tom << ENDat>
These employees are working late. They deserve a bonus:at>
ENDat> [CTRL-d] %
That sends a message to tom at 1:15 a.m. tonight. (This mailer accepts a subject on the command line with its -s option. The output of the w command gives detailed information about logged-in users; not all systems have it.) Unless you understand, the message shouldn't have anything but letters, numbers, commas, and periods.
If your system administrator has set up the program, it's good for easy one-line reminders on particular days. If your UNIX has personal that can send periodic reminders every Tuesday, every hour, or whatever: use the commands in items 1 or 2 above.