style.mdoc
—
FreeBSD manual page style guide
This file specifies the preferred style for manual pages in the
FreeBSD source tree.
- Use literal formatting for examples and literal shell commands, e.g.:
Then run
.Ql make install clean .
which renders as:
Then run ‘make install
clean
’.
The incorrect way would be to use macros like
Nm to stylize the
command invocation:
Then run
.Ql Nm make Cm install Cm clean .
which renders as:
Then run
‘make
install
clean
’.
- The Ql macro
is the preferred macro for formatting literal inline fragments.
Historically, Dq Li was the preferred way before the
deprecation of
Li.
Driver manuals in section four should have a
HARDWARE section describing hardware
known to work with the driver. This section is drawn verbatim into the
Release Hardware Notes, therefore there are several things to note:
- The introductory sentence should be in the form:
The
.Nm
driver supports the following $device_class:
Followed by the list of supported hardware.
This defines what driver the subsection is referring to, and
allows the reader to search through the Hardware Notes not only for the
device models they have, but also for the device type they are looking
to acquire.
- The supported hardware should be listed as a bullet list, or if complexity
requires, a column list. These two list types create very neat subsections
with clean starting and stopping points.
- Format the EXAMPLES section in the
following way:
.Bl -tag -width 0n
.It Sy Example 1\&: Doing Something
.Pp
The following command does something.
.Bd -literal -offset 2n
.Ic # make -VLEGAL
.Ed
.It Sy Example 2\&: Doing Something Different
.Pp
The following command does something different.
.Bd -literal -offset 2n
.Ic # bectl list
.Ed
.Pp
It is good to know this command.
.El
which renders as:
- Example
1: Doing Something
-
The following command does something.
- Example
2: Doing Something Different
-
The following command does something different.
It is good to know this command.
- Do not put whitespace between alternative parameters separated with a pipe
(“|”), e.g.:
.Cm compression Cm on Ns | Ns Cm off
.Cm install Fl -all Ns | Ns Ar portname Ar ...
which in the SYNOPSIS section is rendered as:
compression
on
|off
install
--all
|portname ...
- Use Cm to stylize characters that are command modifiers
(e.g., “,”, “@” or “=”). For
example:
.Sm off
.Fl -meet Cm = Ar who Oo Cm , Ar who " " Ar "..." Oc Cm @ Ar where
.Sm on
which renders as:
--meet
=
who[,
who
...]@
where
instead of:
.Sm off
.Fl -meet No = Ar who Oo , Ar who " " Ar "..." Oc @ Ar where
.Sm on
which would render as:
--meet
=who[,who
...]@where
It is important to realize that in the correct example,
“,”, “@” and “=” are stylized
with Cm. At the same time, the square brackets
(“[]”) are not stylized as they do not belong to the
syntax of the --meet
flag.
- Use the Dq (“”) macro for quoting.
Use the Sq
(‘’) macro for quoting inside quotes. The use of the
Qq
("") macro is usually not necessary.
- Use Va instead of
Dv for
sysctl(8)
variables like kdb.enter.panic.
- Use the angle brackets
Aq
(“<>”) macro for arguments
(Ar) when
they are mixed with similarly stylized macros like
Pa or
Va, e.g.:
.Va critical_filesystems_ Ns Aq Ar type
which renders as:
critical_filesystems_⟨type⟩
instead of:
.Va critical_filesystems_ Ns Ar type
that would be rendered as:
critical_filesystems_type
This manual page first appeared in FreeBSD
13.0.