Home Man
Today's Posts

Linux & Unix Commands - Search Man Pages

OpenSolaris 2009.06 - man page for fonts.conf (opensolaris section 4)

fonts.conf(4)									    fonts.conf(4)

       fonts.conf - Font configuration files

       cc [ flag... ] file... -lfontconfig [ library... ]


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

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

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

       The  intent is to make font configurations relatively static, and shared by as many appli-
       cations 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 provides a format which is  easy  for	external  agents  to  edit  while
       retaining 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 applications 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 configuration of fonts for all applica-
       tions 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
	 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 matching 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 consists of a match predicate and a set of edit-
       ing 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 values 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, pixelsize, 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 precedence in the match  than  lang  ele-
       ments 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 properties found in the
       pattern but not found in the font itself; this permits 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  pattern.
       This modified pattern is returned to the application.

       The return value contains sufficient information to locate and rasterize the font, includ-
       ing 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 simulta-
       neously 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, values 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 controlled 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 application. 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.  Lan-
       guages 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 sup-
       ports 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,  font-
       config  includes per-territory orthographies.  This includes Azerbaijani, Kurdish, Pashto,
       Tigrinya and Chinese.

       Configuration files for fontconfig are stored in XML format; this  format  makes  external
       configuration tools easier to write and ensures that they will generate syntactically cor-
       rect 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 config-
       uration file should contain the following 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 information.  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 maintained by  the  fontconfig  library.	The  default  for  this  file  is
       ``~/.fonts.cache-<version>'',  where <version> is the font configuration file version num-
       ber (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 incorpo-
       rated 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.   <con-
       fig> can contain <blank> and <rescan> elements in any order.

       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  sup-
       posed  to be blank in an <int> element.	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 con-
       figuration files and directories and automatically  rebuild  the  internal  datastructures
       when this interval 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 ele-
       ments 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  sys-
       tem.  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 extensions.
       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"  (substitute  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 tar-
       get="font"> element, the target= attribute in the <test> element selects between  matching
       the  original  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  ele-
       ments).	 The expression elements are evaluated at run-time and modify the property "prop-
       erty".  The modification depends on whether "property" was matched by one of  the  associ-
       ated  <test>  elements,	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>  elements  hold  either
       true or false.  An important limitation exists in the parsing of floating point numbers --
       fontconfig requires that the mantissa 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

       This element holds the four <double> elements of an affine transformation.

       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
	 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 pro-
       duces 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 contain 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> element.

       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 ~/.fonts.conf

       <?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 for-

       conf.d is the conventional name for a directory of additional configuration files  managed
       by  external applications or the local administrator.  The filenames starting with decimal
       digits are sorted in lexicographic 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 files.

       ~/.fonts.conf is the conventional location for per-user font configuration,  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 automatically maintained by fontconfig.

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

       Fontconfig version 2.5.0

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWfontconfig-root	   |
       |Interface Stability	     |Volatile			   |
       |MT-Level		     |See XInitThreads(3X11)	   |

					 13 November 2007			    fonts.conf(4)

All times are GMT -4. The time now is 06:09 PM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
Show Password