Mailx

mailx is a Unix utility program for sending and receiving mail, also known as a Mail User Agent program. Being a console application with a command syntax similar to ed, it is the POSIX standardized variant of the Berkeley Mail utility.

A simplified syntax with some commonly used options might include:

The end of message is indicated by hitting ctrl+d (and/or, dependent on the configuration settings, by writing a line consisting of a single '.'), causing the message to be passed asynchronously to the Mail transport agent. In order to send messages synchronously the mailx internal, POSIX-standardized variable sendwait has to be set, usually in the system-wide initialization file (usually /etc/mail.rc); dependent on the used mailx variant the (nonstandard) command-line option -S can also be used, e.g., mailx -Ssendwait.

By default, users compose messages in mailx line by line, without the use of a text editor. The user may issue a command to mailx by entering a line that begins with a tilde (~). The ~v command causes mailx to invoke a text editor (defined by the VISUAL environment variable) on the message in progress, saved in a temporary file, and likewise for ~e (using the EDITOR environment variable).

Example usage:

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