fonts.conf manpage

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       fonts.conf - Font configuration files


       Fontconfig is a library designed to provide system-wide font configura-
       tion, customization and application access.

       Fontconfig contains two essential  modules,  the	 configuration	module
       which  builds an internal configuration from XML files and the matching
       module which accepts font patterns and  returns	the  nearest  matching

       The  configuration  module  consists of the FcConfig datatype, libexpat
       and FcConfigParse which walks over an XML tree and amends a  configura-
       tion  with  data found within. From an external perspective, configura-
       tion of the library consists of generating a valid XML tree and feeding
       that  to	 FcConfigParse.	 The only other mechanism provided to applica-
       tions for changing the running configuration is to add fonts and direc-
       tories to the list of application-provided font files.

       The intent is to make font configurations relatively static, and shared
       by as many applications as possible. It is hoped that this will lead to
       more  stable  font selection when passing names from one application to
       another.	 XML was chosen as a configuration file format because it pro-
       vides  a format which is easy for external agents to edit while retain-
       ing the correct structure and syntax.

       Font configuration is separate from font matching; applications needing
       to  do  their  own  matching  can  access  the available fonts from the
       library and perform private matching. The intent is to permit  applica-
       tions  to  pick	and  choose appropriate functionality from the library
       instead of forcing them to choose between this library  and  a  private
       configuration mechanism. The hope is that this will ensure that config-
       uration of fonts for all applications can be centralized in one	place.
       Centralizing  font  configuration  will	simplify  and  regularize font
       installation and customization.

       While font patterns may contain essentially any properties,  there  are
       some  well known properties with associated types. Fontconfig uses some
       of these properties for font matching and font completion.  Others  are
       provided as a convenience for the applications' rendering mechanism.

	 Property	 Type	 Description
	 family		 String	 Font family names
	 familylang	 String	 Languages corresponding to each family
	 style		 String	 Font style. Overrides weight and slant
	 stylelang	 String	 Languages corresponding to each style
	 fullname	 String	 Font full names (often includes style)
	 fullnamelang	 String	 Languages corresponding to each fullname
	 slant		 Int	 Italic, oblique or roman
	 weight		 Int	 Light, medium, demibold, bold or black
	 size		 Double	 Point size
	 width		 Int	 Condensed, normal or expanded
	 aspect		 Double	 Stretches glyphs horizontally before hinting
	 pixelsize	 Double	 Pixel size
	 spacing	 Int	 Proportional, dual-width, monospace or charcell
	 foundry	 String	 Font foundry name
	 antialias	 Bool	 Whether glyphs can be antialiased
	 hinting	 Bool	 Whether the rasterizer should use hinting
	 hintstyle	 Int	 Automatic hinting style
	 verticallayout	 Bool	 Use vertical layout
	 autohint	 Bool	 Use autohinter instead of normal hinter
	 globaladvance	 Bool	 Use font global advance data
	 file		 String	 The filename holding the font
	 index		 Int	 The index of the font within the file
	 ftface		 FT_Face Use the specified FreeType face object
	 rasterizer	 String	 Which rasterizer is in use
	 outline	 Bool	 Whether the glyphs are outlines
	 scalable	 Bool	 Whether glyphs can be scaled
	 scale		 Double	 Scale factor for point->pixel conversions
	 dpi		 Double	 Target dots per inch
	 rgba		 Int	 unknown, rgb, bgr, vrgb, vbgr,
				 none - subpixel geometry
	 lcdfilter	 Int	 Type of LCD filter
	 minspace	 Bool	 Eliminate leading from line spacing
	 charset	 CharSet Unicode chars encoded by the font
	 lang		 String	 List of RFC-3066-style languages this
				 font supports
	 fontversion	 Int	 Version number of the font
	 capability	 String	 List of layout capabilities in the font
	 embolden	 Bool	 Rasterizer should synthetically embolden the font

       Fontconfig  performs matching by measuring the distance from a provided
       pattern to all of the available fonts in the system. The closest match-
       ing font is selected. This ensures that a font will always be returned,
       but doesn't ensure that it is anything like the requested pattern.

       Font matching starts  with  an  application  constructed	 pattern.  The
       desired	attributes  of	the resulting font are collected together in a
       pattern. Each property of the pattern can contain one or	 more  values;
       these  are  listed  in  priority order; matches earlier in the list are
       considered "closer" than matches later in the list.

       The initial pattern  is	modified  by  applying	the  list  of  editing
       instructions specific to patterns found in the configuration; each con-
       sists of a match predicate and a set of editing	operations.  They  are
       executed	 in  the  order they appeared in the configuration. Each match
       causes the associated sequence of editing operations to be applied.

       After the pattern has been edited, a sequence of default	 substitutions
       are  performed  to  canonicalize	 the set of available properties; this
       avoids the need for the lower layers to constantly provide default val-
       ues for various font properties during rendering.

       The  canonical  font  pattern  is finally matched against all available
       fonts.  The distance from the pattern to the font is measured for  each
       of  several properties: foundry, charset, family, lang, spacing, pixel-
       size, style, slant, weight, antialias,  rasterizer  and	outline.  This
       list  is	 in priority order -- results of comparing earlier elements of
       this list weigh more heavily than later elements.

       There is one special case to this rule; family names are split into two
       bindings; strong and weak. Strong family names are given greater prece-
       dence in the match than lang elements while weak family names are given
       lower precedence than lang elements. This permits the document language
       to drive font selection when any document specified  font  is  unavail-

       The  pattern representing that font is augmented to include any proper-
       ties found in the pattern but not found in the font itself;  this  per-
       mits  the  application to pass rendering instructions or any other data
       through the matching system. Finally, the list of editing  instructions
       specific	 to  fonts  found in the configuration are applied to the pat-
       tern. This modified pattern is returned to the application.

       The return value contains sufficient information to locate and  raster-
       ize  the	 font, including the file name, pixel size and other rendering
       data. As none of the information	 involved  pertains  to	 the  FreeType
       library,	 applications are free to use any rasterization engine or even
       to take the identified font file and access it directly.

       The match/edit sequences in the	configuration  are  performed  in  two
       passes because there are essentially two different operations necessary
       -- the first is to modify how fonts are selected; aliasing families and
       adding  suitable	 defaults.  The	 second	 is to modify how the selected
       fonts are rasterized. Those must apply to the selected  font,  not  the
       original pattern as false matches will often occur.

       Fontconfig  provides  a	textual	 representation	 for patterns that the
       library can both accept and generate. The representation	 is  in	 three
       parts,  first  a list of family names, second a list of point sizes and
       finally a list of additional properties:

	    <families>-<point sizes>:<name1>=<values1>:<name2>=<values2>...

       Values in a list are separated with commas. The	name  needn't  include
       either  families or point sizes; they can be elided. In addition, there
       are symbolic constants that simultaneously indicate both a name	and  a
       value.  Here are some examples:

	 Name				 Meaning
	 Times-12			 12 point Times Roman
	 Times-12:bold			 12 point Times Bold
	 Courier:italic			 Courier Italic in the default size
	 Monospace:matrix=1 .1 0 1	 The users preferred monospace font
					 with artificial obliquing

       The  '\', '-', ':' and ',' characters in family names must be preceeded
       by a '\' character to avoid having them misinterpreted. Similarly, val-
       ues containing '\', '=', '_', ':' and ',' must also have them preceeded
       by a '\' character. The '\' characters are stripped out of  the	family
       name and values as the font name is read.

       To  help	 diagnose  font and applications problems, fontconfig is built
       with a large amount of internal debugging  left	enabled.  It  is  con-
       trolled	by  means  of  the FC_DEBUG environment variable. The value of
       this variable is interpreted as a number,  and  each  bit  within  that
       value controls different debugging messages.

	 Name	      Value    Meaning
	 MATCH		  1    Brief information about font matching
	 MATCHV		  2    Extensive font matching information
	 EDIT		  4    Monitor match/test/edit execution
	 FONTSET	  8    Track loading of font information at startup
	 CACHE		 16    Watch cache files being written
	 CACHEV		 32    Extensive cache file writing information
	 PARSE		 64    (no longer in use)
	 SCAN		128    Watch font files being scanned to build caches
	 SCANV		256    Verbose font file scanning information
	 MEMORY		512    Monitor fontconfig memory usage
	 CONFIG	       1024    Monitor which config files are loaded
	 LANGSET       2048    Dump char sets used to construct lang values
	 OBJTYPES      4096    Display message when value typechecks fail

       Add  the value of the desired debug levels together and assign that (in
       base 10) to the FC_DEBUG environment variable before running the appli-
       cation. Output from these statements is sent to stdout.

       Each  font  in  the  database contains a list of languages it supports.
       This is computed by comparing the Unicode coverage of the font with the
       orthography  of	each  language. Languages are tagged using an RFC-3066
       compatible naming and occur in two parts -- the ISO  639	 language  tag
       followed a hyphen and then by the ISO 3166 country code. The hyphen and
       country code may be elided.

       Fontconfig has orthographies  for  several  languages  built  into  the
       library.	  No  provision	 has  been made for adding new ones aside from
       rebuilding the library. It currently supports 122 of the 139  languages
       named in ISO 639-1, 141 of the languages with two-letter codes from ISO
       639-2 and another 30 languages with only three-letter codes.  Languages
       with  both  two	and  three letter codes are provided with only the two
       letter code.

       For languages used in multiple  territories  with  radically  different
       character  sets,	 fontconfig includes per-territory orthographies. This
       includes Azerbaijani, Kurdish, Pashto, Tigrinya and Chinese.

       Configuration files for fontconfig are stored in XML format; this  for-
       mat makes external configuration tools easier to write and ensures that
       they will generate syntactically correct configuration  files.  As  XML
       files  are  plain text, they can also be manipulated by the expert user
       using a text editor.

       The fontconfig document type definition resides in the external	entity
       "fonts.dtd";  this is normally stored in the default font configuration
       directory (/etc/fonts). Each configuration file should contain the fol-
       lowing structure:

	    <?xml version="1.0"?>
	    <!DOCTYPE fontconfig SYSTEM "fonts.dtd">

       This  is the top level element for a font configuration and can contain
       <dir>, <cache>, <include>, <match> and <alias> elements in any order.

       This element contains a directory name which will be scanned  for  font
       files to include in the set of available fonts.

       This element contains a file name for the per-user cache of font infor-
       mation. If it starts with '~', it refers to a file in  the  users  home
       directory. This file is used to hold information about fonts that isn't
       present in the per-directory cache files.  It  is  automatically	 main-
       tained  by  the	fontconfig  library.  The  default  for	 this  file is
       ``~/.fonts.cache-<version>'', where <version> is the font configuration
       file version number (currently 2).

       This  element  contains the name of an additional configuration file or
       directory. If a directory, every file within  that  directory  starting
       with  an	 ASCII	digit  (U+0030	-  U+0039)  and ending with the string
       ``.conf'' will be processed in sorted order. When the XML  datatype  is
       traversed  by  FcConfigParse,  the contents of the file(s) will also be
       incorporated into the  configuration  by	 passing  the  filename(s)  to
       FcConfigLoadAndParse.  If  'ignore_missing'  is set to "yes" instead of
       the default "no", a missing file or directory will  elicit  no  warning
       message from the library.

       This  element  provides a place to consolidate additional configuration
       information. <config> can contain <blank> and <rescan> elements in  any

       Fonts  often  include  "broken" glyphs which appear in the encoding but
       are drawn as blanks on the screen. Within the  <blank>  element,	 place
       each  Unicode characters which is supposed to be blank in an <int> ele-
       ment.  Characters outside of this set which are drawn as blank will  be
       elided from the set of characters supported by the font.

       The <rescan> element holds an <int> element which indicates the default
       interval between	 automatic  checks  for	 font  configuration  changes.
       Fontconfig will validate all of the configuration files and directories
       and automatically rebuild the internal datastructures when this	inter-
       val passes.

       This  element  is  used	to black/white list fonts from being listed or
       matched against. It holds acceptfont and rejectfont elements.

       Fonts matched by an acceptfont element are  "whitelisted";  such	 fonts
       are  explicitly	included  in the set of fonts used to resolve list and
       match requests; including them in this list protects  them  from	 being
       "blacklisted" by a rejectfont element. Acceptfont elements include glob
       and pattern elements which are used to match fonts.

       Fonts matched by an rejectfont element are  "blacklisted";  such	 fonts
       are  excluded  from  the	 set  of  fonts used to resolve list and match
       requests as if they didn't exist in  the	 system.  Rejectfont  elements
       include glob and pattern elements which are used to match fonts.

       Glob  elements hold shell-style filename matching patterns (including ?
       and *) which match fonts based on their complete pathnames. This can be
       used  to	 exclude a set of directories (/usr/share/fonts/uglyfont*), or
       particular font file types (*.pcf.gz), but the latter mechanism	relies
       rather  heavily	on  filenaming conventions which can't be relied upon.
       Note that globs only apply to directories, not to individual fonts.

       Pattern elements perform list-style matching on	incoming  fonts;  that
       is, they hold a list of elements and associated values. If all of those
       elements have a matching value, then the pattern matches the font. This
       can  be used to select fonts based on attributes of the font (scalable,
       bold, etc), which is a more reliable mechanism than using  file	exten-
       sions.  Pattern elements include patelt elements.

       Patelt  elements hold a single pattern element and list of values. They
       must have a 'name' attribute which indicates the pattern element	 name.
       Patelt  elements include int, double, string, matrix, bool, charset and
       const elements.

       This element holds first a (possibly empty) list of <test> elements and
       then  a	(possibly empty) list of <edit> elements. Patterns which match
       all of the tests are subjected to all the edits. If 'target' is set  to
       "font"  instead	of the default "pattern", then this element applies to
       the font name resulting from a match rather than a font pattern	to  be
       matched.	 If  'target' is set to "scan", then this element applies when
       the font is scanned to build the fontconfig database.

       This element contains a single value which is compared with the	target
       ('pattern',  'font',  'scan' or 'default') property "property" (substi-
       tute any of the property names seen above). 'compare'  can  be  one  of
       "eq",  "not_eq",	 "less",  "less_eq",  "more", or "more_eq". 'qual' may
       either be the default, "any", in which case the match succeeds  if  any
       value associated with the property matches the test value, or "all", in
       which case all of the values associated with the	 property  must	 match
       the  test value. When used in a <match target="font"> element, the tar-
       get= attribute in the <test> element selects between matching the orig-
       inal  pattern or the font. "default" selects whichever target the outer
       <match> element has selected.

       This element contains a list of expression elements (any of  the	 value
       or  operator  elements).	 The expression elements are evaluated at run-
       time and modify the property "property". The  modification  depends  on
       whether	"property"  was	 matched  by one of the associated <test> ele-
       ments, if so, the modification may affect the first matched value.  Any
       values  inserted	 into  the  property  are  given the indicated binding
       ("strong", "weak" or "same") with "same" binding using the  value  from
       the matched pattern element.  'mode' is one of:

	 Mode			 With Match		 Without Match
	 "assign"		 Replace matching value	 Replace all values
	 "assign_replace"	 Replace all values	 Replace all values
	 "prepend"		 Insert before matching	 Insert at head of list
	 "prepend_first"	 Insert at head of list	 Insert at head of list
	 "append"		 Append after matching	 Append at end of list
	 "append_last"		 Append at end of list	 Append at end of list

       These  elements	hold a single value of the indicated type. <bool> ele-
       ments hold either true or false. An important limitation exists in  the
       parsing	of floating point numbers -- fontconfig requires that the man-
       tissa start with a digit, not a decimal point, so insert a leading zero
       for  purely  fractional	values	(e.g.  use  0.5 instead of .5 and -0.5
       instead of -.5).

       This element holds the four <double> elements of an affine  transforma-

       Holds  a	 property name. Evaluates to the first value from the property
       of the font, not the pattern.

       Holds the name of a constant; these are always integers	and  serve  as
       symbolic names for common font values:

	 Constant	 Property	 Value
	 thin		 weight		 0
	 extralight	 weight		 40
	 ultralight	 weight		 40
	 light		 weight		 50
	 book		 weight		 75
	 regular	 weight		 80
	 normal		 weight		 80
	 medium		 weight		 100
	 demibold	 weight		 180
	 semibold	 weight		 180
	 bold		 weight		 200
	 extrabold	 weight		 205
	 black		 weight		 210
	 heavy		 weight		 210
	 roman		 slant		 0
	 italic		 slant		 100
	 oblique	 slant		 110
	 ultracondensed	 width		 50
	 extracondensed	 width		 63
	 condensed	 width		 75
	 semicondensed	 width		 87
	 normal		 width		 100
	 semiexpanded	 width		 113
	 expanded	 width		 125
	 extraexpanded	 width		 150
	 ultraexpanded	 width		 200
	 proportional	 spacing	 0
	 dual		 spacing	 90
	 mono		 spacing	 100
	 charcell	 spacing	 110
	 unknown	 rgba		 0
	 rgb		 rgba		 1
	 bgr		 rgba		 2
	 vrgb		 rgba		 3
	 vbgr		 rgba		 4
	 none		 rgba		 5
	 lcdnone	 lcdfilter	 0
	 lcddefault	 lcdfilter	 1
	 lcdlight	 lcdfilter	 2
	 lcdlegacy	 lcdfilter	 3
	 hintnone	 hintstyle	 0
	 hintslight	 hintstyle	 1
	 hintmedium	 hintstyle	 2
	 hintfull	 hintstyle	 3

   <OR>, <AND>, <PLUS>, <MINUS>, <TIMES>, <DIVIDE>
       These  elements perform the specified operation on a list of expression
       elements. <or> and <and> are boolean, not bitwise.

   <EQ>, <NOT_EQ>, <LESS>, <LESS_EQ>, <MORE>, <MORE_EQ>
       These elements compare two values, producing a boolean result.

       Inverts the boolean sense of its one expression element

       This element takes three expression elements; if the value of the first
       is true, it produces the value of the second, otherwise it produces the
       value of the third.

       Alias elements provide a shorthand notation for the set of common match
       operations  needed to substitute one font family for another. They con-
       tain a <family> element followed by  optional  <prefer>,	 <accept>  and
       <default>  elements.  Fonts matching the <family> element are edited to
       prepend the list of <prefer>ed families before the  matching  <family>,
       append the <accept>able families after the matching <family> and append
       the <default> families to the end of the family list.

       Holds a single font family name

       These hold a list of <family> elements to be used by the	 <alias>  ele-

       This is an example of a system-wide configuration file

       <?xml version="1.0"?>
       <!DOCTYPE fontconfig SYSTEM "fonts.dtd">
       <!-- /etc/fonts/fonts.conf file to configure system font access -->
	    Find fonts in these directories

	    Accept deprecated 'mono' alias, replacing it with 'monospace'
       <match target="pattern">
	    <test qual="any" name="family"><string>mono</string></test>
	    <edit name="family" mode="assign"><string>monospace</string></edit>

	    Names not including any well known alias are given 'sans'
       <match target="pattern">
	    <test qual="all" name="family" mode="not_eq">sans</test>
	    <test qual="all" name="family" mode="not_eq">serif</test>
	    <test qual="all" name="family" mode="not_eq">monospace</test>
	    <edit name="family" mode="append_last"><string>sans</string></edit>

	    Load per-user customization file, but don't complain
	    if it doesn't exist
       <include ignore_missing="yes">~/.fonts.conf</include>

	    Load local customization files, but don't complain
	    if there aren't any
       <include ignore_missing="yes">conf.d</include>
       <include ignore_missing="yes">local.conf</include>

	    Alias well known font names to available TrueType fonts.
	    These substitute TrueType faces for similar Type1
	    faces to improve screen appearance.
	    <prefer><family>Times New Roman</family></prefer>
	    <prefer><family>Courier New</family></prefer>

	    Provide required aliases for standard names
	    Do these after the users configuration file so that
	    any aliases there are used preferentially
	    <prefer><family>Times New Roman</family></prefer>
	    <prefer><family>Andale Mono</family></prefer>

       This  is	 an  example  of  a  per-user configuration file that lives in

       <?xml version="1.0"?>
       <!DOCTYPE fontconfig SYSTEM "fonts.dtd">
       <!-- ~/.fonts.conf for per-user font configuration -->

	    Private font directory

	    use rgb sub-pixel ordering to improve glyph appearance on
	    LCD screens.  Changes affecting rendering, but not matching
	    should always use target="font".
       <match target="font">
	    <edit name="rgba" mode="assign"><const>rgb</const></edit>

       fonts.conf  contains  configuration  information	 for  the   fontconfig
       library	consisting  of	directories to look at for font information as
       well as instructions on editing program specified font patterns	before
       attempting to match the available fonts. It is in xml format.

       conf.d  is the conventional name for a directory of additional configu-
       ration files managed by external applications or the local  administra-
       tor.  The  filenames starting with decimal digits are sorted in lexico-
       graphic order and used as additional configuration files. All of	 these
       files  are  in  xml  format. The master fonts.conf file references this
       directory in an <include> directive.

       fonts.dtd is a DTD that	describes  the	format	of  the	 configuration

       ~/.fonts.conf.d	is  the	 conventional name for a per-user directory of
       (typically auto-generated) configuration	 files,	 although  the	actual
       location is specified in the global fonts.conf file.

       ~/.fonts.conf is the conventional location for per-user font configura-
       tion,  although	the  actual  location  is  specified  in  the	global
       fonts.conf file.

       ~/.fonts.cache-*	 is  the  conventional	repository of font information
       that isn't found in the per-directory caches. This  file	 is  automati-
       cally maintained by fontconfig.

       fc-cat(1), fc-cache(1), fc-list(1), fc-match(1), fc-query(1)

       Fontconfig version 2.8.0

			       18 November 2009			 FONTS-CONF(5)