After Larry left, and after several hours (actually more than a few) of research, I have found a free service that can be used to send a "SMS" messages from the Raspberry PI to a Cell Phone, using the "curl" command.
Obviously, An Internet connection is needed for the PI, and the "curl" command must be installed (if not already).
$ sudo apt-get install curl
The free SMS service is provided by "textbelt.com" (thanks, textbelt !).
There are limitations to the "textbelt.com" service; no more than 75 messages sent per day from a single IP Address, and no more than 3 messages per 3 minutes can be sent to a single Cell Phone number. For most typical use, this should not be a problem.
Note: the SMS messages received by the Cell Phone will be delivered from "firstname.lastname@example.org".
Usage: on the command line or shell script:
$ curl http://textbelt.com/text -d "number=AAAPPPNNNN" -d "message=This is a test message"
Where "AAAPPPNNNN" is the: Cell Phone Number, AreaCode, Prefix, and Number. Also, dashes ("-") can be used within the phone number, as: "number=202-555-1212"
Note: the words "number=" and "message=" must be used as shown.
For Canada and International use see: Web page.
- Have Fun with PI Messaging !
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