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The tmac files are normal roff source documents, except that they usually contain only definitions and setup commands, but no text. All tmac files are kept in a single or a small number of directories, the tmac directories.
or
fails. Exception to this is the use of man pages written with either the mdoc or the man macro package. See below the description of the andoc.tmac file.
Note that it can happen that some input encoding characters are not available for a particular output device. For example, saying
groff -Tlatin1 -mlatin9 ...
fails if you use the Euro character in the input. Usually, this limitation is present only for devices which have a limited set of output glyphs (-Tascii, -Tlatin1); for other devices it is usually sufficient to install proper fonts which contain the necessary glyphs.
.- [-L|-R|-C|-I n] file [width [height]]
For example, the macro package for the man pages was called man, while its macro file tmac.an. So it could be activated by the argument an to option -m, or -man for short.
For similar reasons, macro packages that did not start with an ‘m’ had a leading ‘m’ added in the documentation and in speech; for example, the package corresponding to tmac.doc was called mdoc in the documentation, although a more suitable name would be doc. For, when omitting the space between the option and its argument, the command line option for activating this package reads -mdoc.
To cope with all situations, actual versions of groff(1) are smart about both naming schemes by providing two macro files for the inflicted macro packages; one with a leading ‘m’ the other one without it. So in groff, the man macro package may be specified as on of the following four methods:
Recent packages that do not start with ‘m’ do not use an additional ‘m’ in the documentation. For example, the www macro package may be specified only as one of the two methods:
Obviously, variants like -mmwww would not make much sense.
A second strange feature of classical troff was to name macro files in the form B]tmac.]I]name]. In modern operating systems, the type of a file is specified as a postfix, the file name extension. Again, groff copes with this situation by searching both anything.tmac and tmac.anything if only anything is specified.
The easiest way to find out which macro packages are available on a system is to check the man~page groff(1) , or the contents of the tmac directories.
In groff, most macro packages are described in~man pages called groff_I]name](7), with a leading ‘m’ for the classical packages.
Alternatively, it is also possible to include a macro file by adding the request .so filename into the document; the argument must be the full file name of an existing file, possibly with the directory where it is kept. In groff, this was improved by the similar request .mso package, which added searching in the tmac path, just like option -m does.
Note that in order to resolve the .so and .mso requests, the roff preprocessor soelim(1) must be called if the files to be included need preprocessing. This can be done either directly by a pipeline on the command line or by using the troff/groff option -s. man calls soelim automatically.
For example, suppose a macro file is stored as
and is used in some document called docu.roff.
At run-time, the formatter call for this is
To include the macro file directly in the document either
is used or
In both cases, the formatter should be called with option -s to invoke soelim.
If you want to write your own groff macro file, call it whatever.tmac and put it in some directory of the tmac path, see section FILES. Then documents can include it with the .mso request or the option -m.
To give a document a personal style, it is most useful to extend the existing elements by defining some macros for repeating tasks; the best place for this is near the beginning of the document or in a separate file.
Macros without arguments are just like strings. But the full power of macros reveals when arguments are passed with a macro call. Within the macro definition, the arguments are available as the escape sequences [rs]$1, Ellipsis], [rs]$9, [rs]$[Ellipsis]], [rs]$*, and [rs]$@, the name under which the macro was called is in [rs]$0, and the number of arguments is in register [rs]n[.$]; see groff(7) .
In this phase, groff interprets all backslashes; that means that all escape sequences in the macro body are interpreted and replaced by their value. For constant expressions, this is wanted, but strings and registers that might change between calls of the macro must be protected from being evaluated. This is most easily done by doubling the backslash that introduces the escape sequence. This doubling is most important for the positional parameters. For example, to print information on the arguments that were passed to the macro to the terminal, define a macro named ‘.print_args’, say.
When calling this macro by
the following text is printed to the terminal:
Let’s analyze each backslash in the macro definition. As the positional parameters and the number of arguments change with each call of the macro their leading backslash must be doubled, which results in [rs][rs]$* and [rs][rs][.$]. The same applies to the macro name because it could be called with an alias name, so [rs][rs]$0.
On the other hand, midpart is a constant string, it does not change, so no doubling for [rs]*[midpart]. The [rs]f escape sequences are predefined groff elements for setting the font within the text. Of course, this behavior does not change, so no doubling with [rs]f[I] and [rs]f[].
Unfortunately, draft mode cannot be used universally. Although it is good enough for defining normal macros, draft mode fails with advanced applications, such as indirectly defined strings, registers, etc. An optimal way is to define and test all macros in draft mode and then do the backslash doubling as a final step; do not forget to remove the .eo request.
- .de c
- .. .c This is like a comment line.
In their simplest form, diversions are multi-line strings, but they get their power when diversions are used dynamically within macros. The (formatted) information stored in a diversion can be retrieved by calling the diversion just like a macro.
Most of the problems arising with diversions can be avoided if you remain aware of the fact that diversions always store complete lines. If diversions are used when the line buffer has not been flushed, strange results are produced; not knowing this, many people get desperate about diversions. To ensure that a diversion works, line breaks should be added at the right places. To be on the secure side, enclose everything that has to do with diversions into a pair of line breaks; for example, by explicitly using .br requests. This rule should be applied to diversion definition, both inside and outside, and to all calls of diversions. This is a bit of overkill, but it works nicely.
[If you really need diversions which should ignore the current partial line, use environments to save the current partial line and/:or use the .box request.]
The most powerful feature using diversions is to start a diversion within a macro definition and end it within another macro. Then everything between each call of this macro pair is stored within the diversion and can be manipulated from within the macros.
The macro files are kept in the tmac directories; a colon separated list of these constitutes the tmac path.
The search sequence for macro files is (in that order):
- /usr/lib/groff/site-tmac
- /usr/share/groff/site-tmac
- /usr/share/groff/1.22.2/tmac
This document is distributed under the terms of the FDL (GNU Free Documentation License) version 1.3 or later. You should have received a copy of the FDL on your system, it is also available on-line at the GNU copyleft site
This document is part of groff, the GNU roff distribution. It was written by Bernd Warken it is maintained by Werner Lemberg
The Filesystem Hierarchy Standard is available at the FHS web site