The mail program (equivalently, Mail)^[20] is a quick, simple email client. Most people want a more powerful program for regular use, but for quick messages from the command line or in scripts, mail is really handy.

To send a quick message:

$ mail [email protected]
Subject: my subject
I'm typing a message.
To end it, I type a period by itself on a line.

.
Cc: [email protected]
$

To send a quick message using a single command, use a pipeline:

$ echo "Hello world" | mail -s "subject" [email protected]

To mail a file using a single command, you can use redirection or a pipeline:

$ mail -s "my subject" [email protected] < filename
$ cat filename | mail -s "my subject" [email protected]

Notice how easily you can send the output of a pipeline as an email message; this is useful in scripts.

Useful options