GROFF_TMAC(5)                                                    GROFF_TMAC(5)



NAME
       groff_tmac - macro files in the roff typesetting system

DESCRIPTION
       The  roff(7) type-setting system provides a set of macro packages suit-
       able for special kinds of documents.  Each  macro  package  stores  its
       macros  and  definitions in a file called the package's tmac file.  The
       name is deduced from `TroffMACros'.

       The tmac files are normal roff source documents, except that they  usu-
       ally  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.

GROFF MACRO PACKAGES
       groff  provides  all classical macro packages, some more full packages,
       and some secondary packages for special purposes.  Note that it is  not
       possible  to use multiple primary macro packages at the same time; say-
       ing e.g.

              sh# groff -m man -m ms foo

       or

              sh# groff -m man foo -m ms bar

       will fail.

   Man Pages
       man    This is the  classical  macro  package  for  UNIX  manual  pages
              (man   pages);   it   is  quite  handy  and  easy  to  use;  see
              groff_man(7).

       doc
       mdoc   An alternative macro package for man pages mainly  used  in  BSD
              systems;  it provides many new features, but it is not the stan-
              dard for man pages; see groff_mdoc(7).

   Full Packages
       The packages in this section provide a complete set of macros for writ-
       ing  documents  of  any  kind,  up to whole books.  They are similar in
       functionality; it is a matter of taste which one to use.

       me     The classical me macro package; see groff_me(7).

       mm     The semi-classical mm macro package; see groff_mm(7).

       mom    The new mom macro package, only available in groff.  As this  is
              not  based  on other packages, it can be freely designed.  So it
              is expected to become quite a nice, modern macro  package.   See
              groff_mom(7).

       ms     The classical ms macro package; see groff_ms(7).

   Special Packages
       The macro packages in this section are not intended for stand-alone us-
       age, but can be used to add special functionality to  any  other  macro
       package or to plain groff.

       papersize
              This  macro  file  is  already loaded at start-up by troff so it
              isn't necessary to call it explicitly.  It provides an interface
              to  set  the  paper  size  on  the  command line with the option
              -dpaper=size.  Possible values for size are the same as the pre-
              defined  papersize  values in the DESC file (only lowercase; see
              groff_font(5) for more) except a7-d7.  An appended l (ell) char-
              acter  denotes  landscape  orientation.  Examples: a4, c3l, let-
              terl.

              Most output drivers need additional command line switches -p and
              -l  to  override the default paper length and orientation as set
              in the driver specific DESC file.  For example, use the  follow-
              ing for PS output on A4 paper in landscape orientation:

              sh# groff -Tps -dpaper=a4l -P-pa4 -P-l -ms foo.ms > foo.ps

       pic    This  file provides proper definitions for the macros PS and PE,
              needed for the pic(1) preprocessor.  They will center each  pic-
              ture.   Use it only if your macro package doesn't provide proper
              definitions for those two macros (actually, most of them already
              have).

       pspic  A  single  macro  is  provided in this file, PSPIC, to include a
              PostScript graphic in a document.  It makes only sense for  out-
              put  devices  which support inclusion of PS images: -Tps, -Tdvi,
              and -Thtml; the file is then loaded automatically.  Syntax:

                     .PSPIC [-L|-R|-I n] file [width [height]]

              file is the name of the file containing the illustration;  width
              and  height  give  the  desired width and height of the graphic.
              The width and height arguments may have scaling  indicators  at-
              tached;  the  default  scaling  indicator is i.  This macro will
              scale the graphic uniformly in the x and y directions so that it
              is  no  more  than  width wide and height high.  By default, the
              graphic will be horizontally centered.  The -L  and  -R  options
              cause  the graphic to be left-aligned and right-aligned, respec-
              tively.  The -I option causes the graphic to be  indented  by  n
              (default scaling indicator is m).

       trace  Use  this for tracing macro calls.  It is only useful for debug-
              ging.  See groff_trace(7).

       tty-char
              Overrides the definition of standard troff characters  and  some
              groff characters for tty devices.  The optical appearance is in-
              tentionally inferior compared to that of normal  tty  formatting
              to allow processing with critical equipment.

       www    Additions  of elements known from the html format, as being used
              in the internet (World Wide Web) pages; this includes URL  links
              and mail addresses; see groff_www(7).

NAMING
       In  classical  roff  systems, there was a funny naming scheme for macro
       packages, due to a simplistic design in option parsing.  Macro packages
       were  always  included by option -m; when this option was directly fol-
       lowed by its argument without an intervening space, this looked like  a
       long  option  preceded by a single minus -- a sensation in the computer
       stone age.  To make this optically working for macro package names, all
       classical  macro  packages  choose  a name that started with the letter
       `m', which was omitted in the naming of the macro file.

       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 talking; for example,
       the package corresponding to tmac.doc was called mdoc in the documenta-
       tion,  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 inflict-
       ed  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  fol-
       lowing four methods:

              sh# groff -m man
              sh# groff -man
              sh# groff -mman
              sh# groff -m an

       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 speci-
       fied only as one of the two methods:

              sh# groff -m www
              sh# groff -mwww

       Obviously, variants like -mmwww would not make much sense.

       A second strange feature of classical troff was to name macro files ac-
       cording to tmac.name.  In modern operating systems, the type of a  file
       is  specified  as 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_name(7), with a leading `m' for the classical packages.

INCLUSION
       There are several ways to use a macro package in a document.  The clas-
       sical  way  is  to  specify the troff/groff option -m name at run-time;
       this makes the contents of the macro package name available.  In groff,
       the  file  name.tmac  is  searched  within the tmac path; if not found,
       tmac.name will be searched for instead.

       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 pre-
       processor 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
       /usr/share/tmac/macros.tmac  and  is  used  in  some  document   called
       docu.roff.

       At run-time, the formatter call for this is

              sh# groff -m macrofile document.roff

       To include the macro file directly in the document either

              .mso macrofile.tmac

       is used or

              .so /usr/share/tmac/macros.tmac

       In both cases, the formatter is called with

              sh# groff -s docu.roff

       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.

WRITING MACROS
       A  roff(7)  document is a text file that is enriched by predefined for-
       matting constructs, such as requests, escape sequences, strings, numer-
       ic  registers, and macros from a macro package.  These elements are de-
       scribed in roff(7).

       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
       $1, ..., $9, $[...], $*, and $@, the name under  which  the  macro  was
       called  is  in  $0,  and  the number of arguments is in register 0; see
       groff(7).

   Copy-in Mode
       The phase when groff reads a macro is called copy-in mode in roff-talk.
       This  is comparable to the C preprocessing phase during the development
       of a program written in the C language.

       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 expression, this is wanted, but strings  and
       registers that might change between calls of the macro must be protect-
       ed 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  infor-
       mation  on the arguments that were passed to the macro to the terminal,
       define a macro named `.print_args', say.

              .ds midpart was called with
              .de print_args
              .  tm \f[I]\\$0\f[] \\*[midpart] \\n[.$] arguments:
              .  tm \\$*
              ..

       When calling this macro by

              .print_args arg1 arg2

       the following text is printed to the terminal:

              print_args was called with the following 2 arguments:
              arg1 arg2

       Let's analyze each backslash in the macro definition.  As the position-
       al parameters and the number of arguments will change with each call of
       the macro their leading backslash must be  doubled,  which  results  in
       \\$*  and  \\[.$].  The same applies to the macro name because it could
       be called with an alias name, so \\$0.

       On the other hand, midpart is a constant string, it will not change, so
       no  doubling  for  \*[midpart].  The \f escape sequences are predefined
       groff elements for setting the font within the text.  Of  course,  this
       behavior will not change, so no doubling with \f[I] and \f[].

   Draft Mode
       Writing groff macros is easy when the escaping mechanism is temporarily
       disabled.  In groff, this is done by enclosing the macro  definition(s)
       into  a pair of .eo and .ec requests.  Then the body in the macro defi-
       nition is just like a normal part of the document -- text  enhanced  by
       calls  of  requests, macros, strings, registers, etc.  For example, the
       code above can be written in a simpler way by

              .eo
              .ds midpart was called with
              .de print_args
              .  tm \f[I]\$0\f[] \*[midpart] \n[.$] arguments:
              .  tm \$*
              ..
              .ec

       Unfortunately, draft mode cannot be used universally.  Although  it  is
       good  enough  for defining normal macros, draft mode will fail with ad-
       vanced 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.

   Tips for Macro Definitions
       o Start  every line with a dot, for example, by using the groff request
         .nop for text lines, or write your own macro that handles  also  text
         lines with a leading dot.

         .de Text
         .  if (\\n[.$] == 0) \
         .    return
         . nop \)\\$*[rs]
         ..

       o Write a comment macro that works both for copy-in and draft mode; for
         as escaping is off in draft mode, trouble  might  occur  when  normal
         comments are used.  For example, the following macro just ignores its
         arguments, so it acts like a comment line:

         .de c
         ..
         .c This is like a comment line.

       o In long macro definitions, make ample use of comment lines  or  empty
         lines for a better structuring.

       o To  increase  readability,  use  groff's indentation facility for re-
         quests and macro calls (arbitrary whitespace after the leading  dot).

   Diversions
       Diversions  can  be  used  to  realize  quite advanced programming con-
       structs.  They are comparable to pointers to large data  structures  in
       the C programming language, but their usage is quite different.

       In their simplest form, diversions are multi-line strings, but they get
       their power when diversions are used dynamically  within  macros.   The
       information  stored  in a diversion can be retrieved by calling the di-
       version just like a macro.

       Most of the problems arising with diversions can be avoided if you  are
       conscious  about  the  fact  that  diversions always deal with complete
       lines.  If diversions are used  when  the  line  buffer  has  not  been
       flashed,  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 amply 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 every-
       thing  between each call of this macro pair is stored within the diver-
       sion and can be manipulated from within the macros.

FILES
       All macro names must be named name.tmac to fully use  the  tmac  mecha-
       nism.   tmac.name  as  with classical packages is possible as well, but
       deprecated.

       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):

       o the directories specified with troff/groff's -M command line option

       o the directories given in the $GROFF_TMAC_PATH environment variable

       o the  current  directory  (only if in unsafe mode, which is enabled by
         the -U command line switch)

       o the home directory

       o a platform-specific directory, being /usr/share/tmac in this  instal-
         lation

       o a     site-specific     (platform-independent)    directory,    being
         /usr/share/tmac in this installation

       o the main tmac directory, being /usr/share/tmac in this installation

ENVIRONMENT
       $GROFF_TMAC_PATH
              A colon separated list of additional tmac directories  in  which
              to  search  for macro files.  See the previous section for a de-
              tailed description.

AUTHOR
       Copyright (C) 2000, 2001, 2002, 2003, 2004  Free  Software  Foundation,
       Inc.

       This document is distributed under the terms of the FDL (GNU Free Docu-
       mentation License) version 1.1 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 <http://www.gnu.org/copyleft/fdl.html>.

       This document is part of groff, the  GNU  roff  distribution.   It  was
       written  by  Bernd Warken <bwarken@mayn.de>; it is maintained by Werner
       Lemberg <wl@gnu.org>.

SEE ALSO
       A complete reference for all parts of the groff system is found in  the
       groff info(1) file.

       groff(1)
              an overview of the groff system.

       groff_man(7),
       groff_mdoc(7),
       groff_me(7),
       groff_mm(7),
       groff_mom(7),
       groff_ms(7),
       groff_trace(7),
       groff_www(7).
              the groff tmac macro packages.

       groff(7)
              the groff language.

       The Filesystem Hierarchy Standard is available at the FHS web site
       <http://www.pathname.com/fhs/>.



Groff Version 1.19.2            6 February 2006                  GROFF_TMAC(5)
