Programming Internet Email

Designing a MIME-Capable Replacement for /bin/mail

Many people send email from CGI scripts or from cron jobs. Wouldn’t life be better if that mail were MIME compliant? For example, a cron job that checks for errors in a log might attach the log for review by a remote administrator. Here we will show how a Perl script can be created that fills this role, as a replacement for /bin/mail, the most likely candidate for replacement. Unlike /bin/mail, though, it would be good if our cross-platform Perl interpreter could run a cross-platform script. That can be accomplished by speaking SMTP directly to a mail server, instead of relying on locally installed mail software that could be system dependent.

The Unix /bin/mail program can be used to send simple text mail messages. The command-line syntax accepted by /bin/mail when used for sending mail is:

mail [-iInv] [-s subject] [-c cc-addr] [-b bcc-addr] to-addr...

The options are described in the man page as follows:

-i

Ignore tty interrupt signals. This is particularly useful when using mail on noisy phone lines.

-I

Forces mail to run in interactive mode even when input isn’t a terminal. In particular, the “~” special character when sending mail is only active in interactive mode.

-n

Inhibits reading /etc/mail.rc upon startup.

-v

Verbose mode. The details of delivery are displayed on the user’s terminal.

-s

Specify subject on command line (only the first argument after the -s flag is used as a subject; be careful to quote subjects containing spaces). ...