Hello, groff group,
the filename extensions for files using the roff language are not
documented. As there are many of these, a kind of standard should be
implemented. I propose the following description as a man-page
"groff-filenames.7"0. It should go to groff/man/groff-filenames.man
Please tell me if I missed something.
Bernd Warken
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groff-filenames.7
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Since the evolution of roff in the 1970s, a whole bunch of file name
extensions for roff files were used. They refer to the roff
preprocessors or macro packages. These extensions are fixed in all
Unix-like operating systems.
Later on groff added some more extensions. We will now write a
man-page about these filename extensions. It should become some type
of standard that can be included in the Emacs nroff-mode or in
programs like "file".
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Compression
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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>]".
Mostly 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>".
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Man-pages
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The "<extension>" for man-pages has the structure
".<section>[<group>]".
##### sections
The traditional "<section>" is a digit from 1 to 8.
<name>.1
<name>.2
<name>.3
<name>.4
<name>.5
<name>.6
<name>.7
<name>.8
Classic man-page sections.
Linux added the section number 9 for kernel man-pages.
<name>.9
Linux kernel man-pages
In older commercial Unix systems, the 3 characters n, o, or l were
also used as section names. This is today deprecated, but there are
still documents in this format.
<name>.n
<name>.o
<name>.l
Deprecated old sections.
###### 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 documents or "tk" to
refer to the tk programming language.
Examples:
groff.1 is the man-page for "groff" in section "1" without
a group
xargs.1posix.gz is the man-page for "xargs" in section "1" and group
"posix"; moreover it is compressed with "gz".
config.5ssl OpenSSL CONF library configuration files from
section "5" with group "ssl".
dpkg-reconfigure.8cdebconf
man-page for "dpkg-reconfigure" in section 8 and
group "cdebconf".
##### source of man pages
There are 2 styles for writing man pages: "man" and "mdoc". These 2
extensions are used in the source code package of groff.
<name>.man traditional man-page format
<name>.mdoc additional man-page format
<name>.mandoc recognizing both man-page formats
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Traditional troff extensions
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##### macro packages
Traditional troff used the following extensions for the macro package
used in the file:
<name>.me roff file using the "me" macro package
<name>.mm roff file using the "mm" macro package
<name>.ms roff file using the "ms" macro package
##### preprocessors
Moreover the following preprocessors were used as filename extrension:
<name>.chem for the integration of chemical formulas
<name>.eqn for the mathematical use of equations
<name>.pic graphical tool
<name>.tbl for tables with tbl
<name>.ref for files using the prefer preprocesor
##### classical roff files
<name>.t
<name>.tr
for files using the roff language of any kind
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New groff extensions
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GNU roff groff is the actual roff standard. So we should add necessary
extensions. I propose the following instead of ".t" or ".tr":
<name>.groff
<name>.roff
general ending for files using the "groff" language
<name>.mmse file with swedish "mm" makros for groff
<name>.mom files written in the groff macro package "mom"
<name>.www files written in HTML-like groff macros
<name>.grap files written for the graphical "grap" processor.
<name>.grn for including gremlin(1) pictures,
<name>.RUNOFF for files in the historical "RUNOFF" format of the 1960s
