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Updated: Wednesday, February 9, 2022

groff_font (5)


groff_font - format of groff device and font description files


Please see following description for synopsis


GROFF_FONT(5)                 File Formats Manual                GROFF_FONT(5)

       groff_font - format of groff device and font description files

       The groff font format is roughly a superset of the ditroff font format.
       The font files for device name  are  stored  in  a  directory  devname.
       There  are two types of file: a device description file called DESC and
       for each font F a font file called F.  These are text files; unlike the
       ditroff font format, there is no associated binary format.

   DESC file format
       The  DESC  file can contain the following types of line as shown below.
       Later entries in the file override previous values.

       Empty lines are ignored.

              This line and everything following in the file are ignored.   It
              is allowed for the sake of backwards compatibility.

       family fam
              The default font family is fam.

       fonts n F1 F2 F3 ... Fn
              Fonts  F1,  ...,  Fn are mounted in the font positions m+1, ...,
              m+n where m is the number of styles.  This  command  may  extend
              over  more than one line.  A font name of 0 causes no font to be
              mounted on the corresponding font position.

       hor n  The horizontal resolution is n machine units.

       image_generator string
              Needed for grohtml only.  It specifies the program  to  generate
              PNG  images from PostScript input.  Under GNU/Linux this is usu-
              ally gs but under other systems (notably cygwin) it might be set
              to another name.

       paperlength n
              The  physical vertical dimension of the output medium in machine
              units.  This isn't used by troff itself but by  output  devices.
              Deprecated.  Use papersize instead.

       papersize string
              Select  a paper size.  Valid values for string are the ISO paper
              types A0-A7, B0-B7, C0-C7, D0-D7, DL, and  the  US  paper  types
              letter, legal, tabloid, ledger, statement, executive, com10, and
              monarch.  Case is not significant for string if it holds  prede-
              fined  paper  types.   Alternatively,  string can be a file name
              (e.g. `/etc/papersize'); if the file can be opened, groff  reads
              the  first  line  and tests for the above paper sizes.  Finally,
              string can be a custom paper size in the format length,width (no
              spaces  before and after the comma).  Both length and width must
              have a unit appended; valid values are `i' for inches,  `c'  for
              centimeters,  `p'  for  points,  and  `P'  for  picas.  Example:
              12c,235p.  An argument which  starts  with  a  digit  is  always
              treated  as a custom paper format.  papersize sets both the ver-
              tical and horizontal dimension of the output medium.

              More than one argument can be specified; groff scans  from  left
              to right and uses the first valid paper specification.

       paperwidth n
              The  physical  horizontal  dimension  of  the  output  medium in
              machine units.  Deprecated.  Use papersize instead.  This  isn't
              used by troff itself but by output devices.

              Make troff tell the driver the source file name being processed.
              This is achieved by another tcommand: F filename.

       postpro program
              Use program as the postprocessor.

       prepro program
              Call program as a preprocessor.

       print program
              Use program as the spooler program for  printing.   If  omitted,
              the -l and -L options of groff are ignored.

       res n  There are n machine units per inch.

       sizes s1 s2 ... sn 0
              This  means  that the device has fonts at s1, s2, ..., sn scaled
              points.  The list of sizes must be terminated by a 0.   Each  si
              can also be a range of sizes m-n.  The list can extend over more
              than one line.

       sizescale n
              The scale factor for point sizes.  By default this has  a  value
              of  1.  One scaled point is equal to one point/n.  The arguments
              to the unitwidth and sizes commands are given in scaled points.

       styles S1 S2 ... Sm
              The first m font positions are associated with styles  S1,  ...,

              This  means that the postprocessor can handle the t and u output

              Indicate that the output device supports  the  complete  Unicode
              repertoire.   Useful  only  for  devices which produce character
              entities instead of glyphs.

              If unicode is present, no charset section  is  required  in  the
              font  description  files  since  the Unicode handling built into
              groff is used.  However, if there are entries in a charset  sec-
              tion,  they  either override the default mappings for those par-
              ticular characters or add new mappings (normally  for  composite

              This is used for -Tutf8, -Thtml, and -Txhtml.

       unitwidth n
              Quantities  in  the  font  files  are given in machine units for
              fonts whose point size is n scaled points.

              Make the font  handling  module  always  return  unscaled  glyph
              widths.  Needed for the grohtml device.

              This  command  indicates  that  troff should encode named glyphs
              inside special commands.

       vert n The vertical resolution is n machine units.

       The res, unitwidth, fonts, and sizes lines  are  compulsory.   Not  all
       commands  in  the  DESC file are used by troff itself; some of the key-
       words (or even additional ones) are used  by  postprocessors  to  store
       arbitrary information about the device.

       Here a list of obsolete keywords which are recognized by groff but com-
       pletely ignored: spare1, spare2, biggestfont.

   Font file format
       A font file has two sections; empty lines are ignored in both of them.

       The first section is a sequence of lines each containing a sequence  of
       blank  delimited words; the first word in the line is a key, and subse-
       quent words give a value for that key.

       ligatures lig1 lig2 ... lign [0]
              Glyphs lig1, lig2, ..., lign are ligatures;  possible  ligatures
              are  ff, fi, fl, ffi, and ffl.  For backwards compatibility, the
              list of ligatures may be terminated with a 0.  The list of liga-
              tures may not extend over more than one line.

       name F The name of the font is F.

       slant n
              The  glyphs  of  the  font have a slant of n degrees.  (Positive
              means forward.)

       spacewidth n
              The normal width of a space is n.

              The font is special; this means that when a glyph  is  requested
              that  is  not present in the current font, it is searched for in
              any special fonts that are mounted.

       Other commands are ignored by troff but may be used  by  postprocessors
       to store arbitrary information about the font in the font file.

       The first section can contain comments which start with the # character
       and extend to the end of a line.

       The second section contains one or two subsections.  It must contain  a
       charset  subsection  and  it  may  also contain a kernpairs subsection.
       These subsections can appear in any order.  Each subsection starts with
       a word on a line by itself.

       The  word  charset  starts the charset subsection.  The charset line is
       followed by a sequence of lines.  Each line gives information  for  one
       glyph.   A  line  comprises  a  number of fields separated by blanks or
       tabs.  The format is

              name metrics type code [entity_name] [-- comment]

       name identifies the glyph: if name is a single glyph c then  it  corre-
       sponds  to the groff input character c; if it is of the form \c where c
       is a single character, then it corresponds  to  the  special  character
       \[c];  otherwise  it  corresponds to the groff input character \[name].
       If it is exactly two characters xx it can be  entered  as  \(xx.   Note
       that single-letter special characters can't be accessed as \c; the only
       exception is `\-' which is identical to `\[-]'.  The name ---  is  spe-
       cial  and  indicates that the glyph is unnamed; such glyphs can only be
       used by means of the \N escape sequence in troff.

       The type field gives the glyph type:

       1      means the glyph has a descender, for example, `p';

       2      means the glyph has an ascender, for example, `b';

       3      means the glyph has both an ascender and a descender, for  exam-
              ple, `('.

       The code field gives the code which the postprocessor uses to print the
       glyph.  The glyph can also be input to groff using this code  by  means
       of  the \N escape sequence.  The code can be any integer.  If it starts
       with a 0 it is interpreted as octal; if it starts with 0x or 0X  it  is
       interpreted as hexadecimal.  Note, however, that the \N escape sequence
       only accepts a decimal integer.

       The entity_name field gives an ASCII string identifying the glyph which
       the postprocessor uses to print that glyph.  This field is optional and
       is currently used by grops to build sub-encoding arrays  for  PS  fonts
       containing  more than 256 glyphs.  (It has also been used for grohtml's
       entity names but for efficiency  reasons  this  data  is  now  compiled
       directly into grohtml.)

       Anything on the line after the encoding field or `--' are ignored.

       The  metrics field has the form (in one line; it is broken here for the
       sake of readability):


       There must not be any spaces between  these  subfields.   Missing  sub-
       fields  are  assumed  to be 0.  The subfields are all decimal integers.
       Since there is no  associated  binary  format,  these  values  are  not
       required  to  fit  into a variable of type char as they are in ditroff.
       The width subfields gives the width of the glyph.  The height  subfield
       gives  the  height  of the glyph (upwards is positive); if a glyph does
       not extend above the baseline, it should be given a zero height, rather
       than  a  negative  height.   The  depth subfield gives the depth of the
       glyph, that is, the distance below the lowest point below the  baseline
       to which the glyph extends (downwards is positive); if a glyph does not
       extend below above the baseline, it  should  be  given  a  zero  depth,
       rather than a negative depth.  The italic-correction subfield gives the
       amount of space that should be added after the glyph when it is immedi-
       ately  to  be  followed by a glyph from a roman font.  The left-italic-
       correction subfield gives the amount of  space  that  should  be  added
       before  the glyph when it is immediately to be preceded by a glyph from
       a roman font.  The subscript-correction gives the amount of space  that
       should  be  added after a glyph before adding a subscript.  This should
       be less than the italic correction.

       A line in the charset section can also have the format

              name "

       This indicates that name is just another name for the  glyph  mentioned
       in the preceding line.

       The  word  kernpairs  starts  the  kernpairs  section.  This contains a
       sequence of lines of the form:

              c1 c2 n

       This means that when glyph c1  appears  next  to  glyph  c2  the  space
       between  them should be increased by n.  Most entries in kernpairs sec-
       tion have a negative value for n.

              Device description file for device name.

              Font file for font F of device name.

       See attributes(7) for descriptions of the following attributes:

       |Availability   | text/groff       |
       |Stability      | Uncommitted      |

       groff_out(5), troff(1), addftinfo(1), afmtodit(1)

       A man-page name(n) of section n can be viewed either with
              $ man n name
       for text mode or
              $ groffer nname"
       for graphical mode (default is PDF mode).

       Copyright (C) 1989-2014 Free Software Foundation, Inc.

       This file is part of  groff  (GNU  roff),  which  is  a  free  software

       You  can  redistribute  it  and/or modify it under the terms of the GNU
       General Public License as published by the  Free  Software  Foundation,
       either version 2 of the License, or (at your option) any later version.

       You should have received a copy of the GNU General Public License along
       with      this       program.        If       not,       see       GPL2

       Source  code  for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-

       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source                was                downloaded                from

       Further information about this software can be found on the open source
       community website at https://www.gnu.org/software/groff.

Groff Version 1.22.3            4 November 2014                  GROFF_FONT(5)