MAILER.CONF(5)

💌 MAILER.CONF(5) — like, the whole entire vibe 💌

okay so bestie, gather round, because today we're talking about mailer.conf(5) — the File Formats Manual entry for the configuration file that drives mailwrapper(8). yes it's a whole thing and yes it's iconic 🎀

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✨ NAME ✨

mailer.conf — the configuration file for mailwrapper(8) 🦋

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🌸 DESCRIPTION 🌸

okay so the file /etc/mail/mailer.conf is literally just a bunch of lines that look like this:

name program [arguments ...]

The first word of each line? That's the name of a program that invokes mailwrapper(8). Like, on a typical system /usr/sbin/sendmail would be a symbolic link to mailwrapper(8), and so would newaliases(1) and mailq(1). So name might be sendmail or newaliases etc. — you get it 💅

The second word of each line is the name of the program that actually gets executed when that first name is invoked. the real one. the main character 👑

The further arguments, if there are any, get passed to the program — and then, after those, come the arguments mailwrapper(8) was called with. order matters, bestie 🫶

The file can also have comment lines, and those are denoted by a # mark in the first column of any line. first column only, no cap 🤭

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🎀 FILES 🎀

• /etc/mail/mailer.conf

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🔥 EXAMPLES 🔥

This example shows how to set up mailer.conf to invoke the traditional sendmail(8) program:

# Execute the "real" sendmail program located in
# /usr/libexec/sendmail/sendmail
sendmail        /usr/libexec/sendmail/sendmail
mailq           /usr/libexec/sendmail/sendmail
newaliases      /usr/libexec/sendmail/sendmail

Using Postfix (from ports) to replace sendmail(8):

# Emulate sendmail using postfix
sendmail        /usr/local/sbin/sendmail
mailq           /usr/local/sbin/sendmail
newaliases      /usr/local/sbin/sendmail

Using Exim (from ports) to replace sendmail(8):

# Emulate sendmail using exim
sendmail        /usr/local/sbin/exim
mailq           /usr/local/sbin/exim -bp
newaliases      /usr/bin/true
rmail           /usr/local/sbin/exim -i -oee

Using mini_sendmail (from ports) to replace sendmail(8):

# Send outgoing mail to a smart relay using mini_sendmail
sendmail        /usr/local/bin/mini_sendmail -srelayhost

Using dma(8) to replace sendmail(8):

# Execute dma instead of sendmail
sendmail        /usr/libexec/dma
mailq           /usr/libexec/dma
newaliases      /usr/libexec/dma
rmail           /usr/libexec/dma

like, pick your fighter, they're all valid 🌈

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💜 SEE ALSO 💜

• mail(1), mailq(1), newaliases(1), dma(8), mailwrapper(8), sendmail(8)
• postfix(1) (ports/mail/postfix), dma(8) (ports/mail/dma), exim(8) (ports/mail/exim), mini_sendmail(8) (ports/mail/mini_sendmail)

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🦋 HISTORY 🦋

mailer.conf appeared in NetBSD 1.4. a true vintage icon, honestly ✨

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👑 AUTHORS 👑

Perry E. Metzger <perry@piermont.com>

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💀 BUGS 💀

ngl the entire reason this program exists is a crock. 😭 Like, instead, a command for how to submit mail should be standardized, and all the "behave differently if invoked with a different name" behavior of things like mailq(1) should go away. so there's that. screaming, crying, throwing up, etc. 🙈

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and that's the tea, bestie 🍓 this whole page came to you from Debian, dated December 26, 2017 — go forth and configure your mailer, you absolute legend 💖🧚⭐