21 March 2020
groff_filenames - filename extensions for roff and groff
Since the evolution of roff in the 1970s, a whole bunch of filename extensions for roff files were used.
The roff extensions refer to preprocessors or macro packages. These extensions are fixed in all Unix-like operating systems.
Later on, groff added some more extensions. This man page is about these filename extensions.
COMPRESSION OF ROFF FILES
Each roff file can be optionally compressed. That means that the total filename ends with a compressor name. So the whole filename has the structure <name>.<extension>[.<compression>].
Best-known are the compressor extensions .Z, .gz, and .bzip2. Relatively new is .xz.
From now on, we will ignore the compressions and only comment the structure <name>.<extension>.
The Unix manual pages are widely called man pages. The man page style is the best known part of the roff language.
The extensions for man should be better documented. So this is documented here.
Files written in the man language use the following extension: *.<section>[<group>].
Man page Sections
The traditional man page <section> is a digit from 1 to 8.
|<name>.2 <name>.3 <name>.4 <name>.5 <name>.6 <name>.7 <name>.8 Classic man page sections.|
|In older commercial Unix systems, the 3 characters l, n, and o were also used as section names. This is today deprecated, but there are still documents in this format.|
|<name>.n <name>.o Deprecated man page sections, which stood for [lq]local[rq], [lq]new[rq], and [lq]old[rq], respectively.|
Man page Group Extensions
The <group> extension in .<section>[<group>] is optional, but it can be any string of word characters. Usually programmers use a group name that is already used, e.g. x for X Window System documents or tcl to refer to the Tcl programming language.
|is the man page for groff in section 1 without a group|
|is the man page for the program xargs in section 1 and group posix; moreover it is compressed with gz (gzip).|
|OpenSSL CONF library configuration files from section 5 with group ssl.|
|man page for the program dpkg-reconfigure in section 8 and group cdebconf.|
Source of man pages
There are 2 roff languages for writing man pages: man and mdoc.
The names of these 2 styles are taken as extensions for the source code files of man pages in the groff package.
|traditional Unix-like man page format within groff source files.|
|A temporary man page file produced from a name.man man page by a run of make within the groff source package.|
|Man page format in BSD.|
|Man page format in heirloom roff .|
|Files using this extension recognize both man page formats in groff and other processors.|
TRADITIONAL TROFF EXTENSIONS
Files Using Macro Packages
The classical roff languages were interpreted by the traditional troff and nroff programs.
All of these classical roff languages and their extensions are still very active in groff.
There were several roff languages, each represented by a macro-package. Each of these provided a suitable file name extension:
|roff file using the me macro package.|
|roff file using the mm macro package|
|roff file using the ms macro package|
Source Code for Macro Packages (TMAC Files)
In traditional roff the source code for the macro packages was stored in TMAC files. Their file names have the form:
For example, tmac.an is the source for the man macro package.
|<package> is the name of the macro package without the leading m character, which is reintegrated by the option -m.|
In the groff source, more suitable file names were integrated, see later on.
Moreover, the following preprocessors were used as filename extension:
|for the integration of chemical formulas|
|for the mathematical use of equations|
|for tables with tbl|
|for files using the prefer preprocessor|
Classical Roff Files
|<name>.tr for files using the roff language of any kind|
NEW GROFF EXTENSIONS
GNU roff groff is the actual roff standard, both for classical roff and new extensions. So even the used new extensions in the source code should be regarded as actual standard. The following extensions are used instead of classical .t or .tr:
|<name>.roff general ending for files using the groff language|
Source Code for Macro Packages (TMAC Files)
As the classical form tmac.<package_without_m>, of the TMAC file names is quite strange, groff added the following structures:
Files Using new Macro Packages
Groff uses the following new macro packages:
|file with swedish mm macros for groff|
|files written in the groff macro package mom|
|files written in HTML-like groff macros.|
Preprocessors and Postprocessors
This document was written by Bernd Warken
|History and future|
|roff(7), man-pages(7), groff_diff(7), groff(7)|
|uncompress(1posix), gzip2(1), bzip2(1), xz(1)|
|A man page of the naming form name(n) can be read in text mode by|
|man n name or in graphical mode (PDF) by groffer n name|
|Gunnar Ritter’s Heirloom roff project You can get this package with the shell command:|
|\(Do git clone https://github.com/n-t-roff/heirloom-doctools|