.\" $Id$ .\" .\" Copyright (c) 2009 Kristaps Dzonsons .\" .\" Permission to use, copy, modify, and distribute this software for any .\" purpose with or without fee is hereby granted, provided that the .\" above copyright notice and this permission notice appear in all .\" copies. .\" .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL .\" WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED .\" WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE .\" AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL .\" DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR .\" PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER .\" TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR .\" PERFORMANCE OF THIS SOFTWARE. .\" .Dd $Mdocdate$ .Dt manuals 7 .Os .\" SECTION .Sh NAME .Nm Writing UNIX Documentation .Nd a guide to writing UNIX manuals .\" SECTION .Sh DESCRIPTION .Em A utility without good documentation is of no utility at all . .\" PARAGRAPH .Pp A system component's documentation describes the utility of that component, whether it's a device driver, an executable or, most importantly, a game. Although there are plenty of documents available on how to read .Ux documents, or where to find them, few focus on composition. .\" PARAGRAPH .Pp This document serves as a tutorial to writing .Ux documentation .Pq Dq manuals . If you add something to your operating system, whether it's a new file format or directory structure or device driver, it needs documentation. .\" SECTION .Sh COMPOSITION Prepare your composition environment by copying over the manual template from .Pa /usr/share/misc/mdoc.template . .Pp If this file doesn't exist, bug your administrator. .Em \&Do not start afresh or by copying another manual unless you know exactly what you're doing! .\" SUBSECTION .Ss Section Numbering Find an appropriate section for your manual. There may exist multiple manual names per section, so be specific. A table of all available manual sections follows: .Pp .\" LIST .Bl -tag -width "XXXXXXXXXXXX" -offset indent -compact .It Em Section .Em Description .It 1 operator utilities .It 2 system calls .It 3, 3p, 3f programming libraries (C, Perl, Fortran) .It 5 file and wire protocol formats .It 6 games .It 7 tutorials, documents and papers .It 8 administrator utilities .It 9 in-kernel routines .El .Pp If your manual falls into multiple categories, choose the most widely-used or, better, re-consider the topic of your manual to be more specific. You can list all manuals per section by invoking .Xr apropos 1 , then provide the .Fl s flag to .Xr man 1 to see the specific section manual (section 1, in this example): .\" DISPLAY .Bd -literal -offset indent % apropos myname myname (1) - utility description myname (3) - library description % man \-s 1 myname .Ed .\" SUBSECTION .Ss Naming Name your component. Be terse, erring on the side of clarity. You may want to look for other manuals by that same name before committing: .Pp .Dl % apropos myname .Pp Manual files are named .Pa myname.mysection , such as .Pa manuals.7 for this document. .\" SUBSECTION .Ss Input Language Manuals should .Em always be written in the .Xr mdoc 7 formatting language. .Pp There exist other documentation-specific languages, such as the historical .Xr me 7 , .Xr ms 7 and .Xr man 7 packages of .Xr roff 7 ; newer languages such as DocBook, texinfo or schema-driven XML; or even ad-hoc conventions such as README files. .Em Avoid these formats . Historical formats fail to capture a manual's semantic content, instead only modelling its style. Newer methods requires special, system-specific tools and may change or become obsolete over the life-time of your component. .Pp There are two canonical references for writing mdoc. Read them. .Pp .\" LIST .Bl -tag -width XXXXXXXXXXXXXXXX -offset indent -compact .It Xr mdoc 7 formal language reference .It Xr mdoc.samples 7 macro reference .El .Pp Open the template you've copied into .Pa name.section and begin editing. .\" SUBSECTION .Ss Development Tools While writing, make sure that your manual is correctly structured: .Pp .Dl % mandoc \-Tlint \-Wall name.1 .Pp You may spell-check your work as follows: .Pp .Dl % deroff name.1 | spell .Dl % ispell \-n name.1 .Pp Use .Xr cvs 1 or, if not available, .Xr rcs 1 to version-control your work. If you wish the last check-in to effect your document's date, use the following RCS tag for the date macro: .Pp .Dl \&.Dd $Mdocdate$ .Pp If using version control, the first line in your manual should be a comment with the .Li $Id$ rcs tag. .\" SUBSECTION .Ss Viewing mdoc documents may be paged to your terminal with traditional tools such as .Xr nroff 1 , .Xr groff 1 , or with newer, more powerful tools such as .Xr mandoc 1 : .\" DISPLAY .Bd -literal -offset indent % nroff \-mandoc name.1 | less % groff \-Tascii \-mandoc name.1 | less % mandoc name.1 | less .Ed .Pp Other output formats are also supported: .\" DISPLAY .Bd -literal -offset indent % groff \-Tps \-mandoc name.1 | less % mandoc \-Thtml name.1 | less .Ed .\" SUBSECTION .Ss Automation Consider adding your mdoc documents to .Xr make 1 Makefiles in order to automatically check your input and generate output: .Bd -literal -offset indent \&.SUFFIXES: .html .txt .1 .in \&.in.1: mandoc -Wall,error -Tlint $< cp -f $< $@ \&.1.html: mandoc -Thtml $< >$@ \&.1.txt: mandoc -Tascii $< | col -b >$@ .Ed .\" SUBSECTION .Ss Licensing Your manual must have a license. It should be listed at the start of your document, just as in source code. .\" SECTION .Sh BEST PRACTICES The .Xr mdoc 7 and .Xr mdoc.samples 7 files are indispensable in guiding composition. In this section, we introduce some .Ux manual best practices: .\" SUBSECTION .Ss Language .Bl -enum .It Use clear, concise language. Favour simplicity. .It Write your manual in non-idiomatic English. Don't worry about Commonwealth or American spellings \(em just correct ones. .It Spell-check your manual, keeping in mind short-letter terms ( .Xr iwi 4 vs. .Xr iwn 4 ) . .It If you absolutely must use special characters (diacritics, mathematical symbols and so on), use the escapes dictated in .Xr mdoc 7 . .El .\" SUBSECTION .Ss Style The structure of the mdoc language makes it very hard to have any particular format style. Keep your lines under 72 characters in length. If you must have long option lines, use .Sq \&Oo/Oc . .Em \&Do not use .Sq \&Xo/Xc ; instead, either fine another way to write long lines, or, at the absolute worst, use CPP-style newline escapes. .\" SUBSECTION .Ss References Other components may be referenced with the .Sq \&Xr and .Sq \&Sx macros. Make sure that these exist. If you intend to distribute your manual, make sure .Sq \&Xr references are valid across systems (within reason). If you cross-link with .Sq \&Sx , make sure that the section reference exists. .\" SUBSECTION .Ss Citations Cite your work. If your system references standards documents or other publications, please use the .Sq \&Rs/Re block macros. .\" SUBSECTION .Ss Formatting .Em Don't style your manual. Give it meaningful content. The front-end will worry about formatting and style. .\" SECTION .Sh MAINTENANCE As your component changes and bugs are fixed, your manual may become out of date. You may be tempted to use automation tools like Doxygen to smooth the development of your manuals. Don't. Source documentation is different from a component manual.