I use the at command (40.7) to send myself reminders. The at job runs a mail program (1.33) and feeds the body of the message to the mailer's standard input. Examples:
To send a one-line reminder, I use a one-line command like this:
%at 0427 tuesday
at>echo "send summary to Tim today" | mail jpeek@jpeek.com
at> [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 28
at>mail jpeek@jpeek.com < msgfile
at>rm msgfile
at> [CTRL-d] %
Combine the output of UNIX commands and text with backquotes (9.16) and a here document (8.18):
%at 0115
at>mail -s "Hard-working people" tom << END
at>These employees are working late. They deserve a bonus:
at>`w`
at>END
at> [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 how to quote here-document text (45.26), the message shouldn't have anything but letters, numbers, commas, and periods.
If your system administrator has set up the calendar (48.4) program, it's good for easy one-line reminders on particular days. If your UNIX has personal crontabs (40.12) that can send periodic reminders every Tuesday, every hour, or whatever: use the commands in items 1 or 2 above.
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