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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.

              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 will be 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 will cause 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
              usually 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
              predefined 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 vertical and horizontal dimension of the output

              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 pointsizes.  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 will be associated with styles

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

       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 character
              widths.  Needed for the grohtml device.

              This command indicates that troff should encode named characters
              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
       keywords (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
       completely ignored: spare1, spare2, biggestfont.

   Font file format
       A font file has two sections.  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 subsequent words give a value for that key.

       ligatures lig1 lig2...lign [0]
              Characters 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 ligatures may not extend over more than one line.

       name F The name of the font is F.

       slant n
              The characters 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 character is
              requested that is not present in the current font, it will be
              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
       character.  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 character: if name is a single character c then it
       corresponds 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
       special and indicates that the character is unnamed; such characters
       can only be used by means of the \N escape sequence in troff.

       Groff supports eight-bit characters; however some utilities have
       difficulties with eight-bit characters.  For this reason, there is a
       convention that the name charn is equivalent to the single character
       whose code is n.  For example, char163 would be equivalent to the
       character with code 163 which is the pounds sterling sign in ISO

       The type field gives the character type:

       1      means the character has a descender, for example, p;

       2      means the character has an ascender, for example, b;

       3      means the character has both an ascender and a descender, for
              example, (.

       The code field gives the code which the postprocessor uses to print the
       character.  The character 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 will be interpreted as octal; if it starts with 0x
       or 0X it will be intepreted 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 the character.  This field is optional
       and has been introduced so that the html device driver can encode its
       character set.  For example, the character `\[Po]' is represented as
       `£' in html 4.0.

       Anything on the line after the encoding field resp. after `--' will be

       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
       subfields 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 character.  The height
       subfield gives the height of the character (upwards is positive); if a
       character 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 character, that is, the distance below the lowest point
       below the baseline to which the character extends (downwards is
       positive); if a character 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 character when it is immediately to be followed by a
       character from a roman font.  The left-italic-correction subfield gives
       the amount of space that should be added before the character when it
       is immediately to be preceded by a character from a roman font.  The
       subscript-correction gives the amount of space that should be added
       after a character 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 character
       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 character c1 appears next to character c2 the
       space between them should be increased by n.  Most entries in kernpairs
       section will have a negative value for n.

              Device description file for device name.

              Font file for font F of device name.

       groff_out(5), troff(1).

Groff Version 1.19.2           September 4, 2005                 GROFF_FONT(5)