5 fonts.conf -- Font configuration files
12 $XDG_CONFIG_HOME/fontconfig/conf.d
13 $XDG_CONFIG_HOME/fontconfig/fonts.conf
19 Fontconfig is a library designed to provide system-wide font
20 configuration, customization and application access.
24 Fontconfig contains two essential modules, the configuration
25 module which builds an internal configuration from XML files
26 and the matching module which accepts font patterns and returns
27 the nearest matching font.
31 The configuration module consists of the FcConfig datatype,
32 libexpat and FcConfigParse which walks over an XML tree and
33 amends a configuration with data found within. From an external
34 perspective, configuration of the library consists of
35 generating a valid XML tree and feeding that to FcConfigParse.
36 The only other mechanism provided to applications for changing
37 the running configuration is to add fonts and directories to
38 the list of application-provided font files.
40 The intent is to make font configurations relatively static,
41 and shared by as many applications as possible. It is hoped
42 that this will lead to more stable font selection when passing
43 names from one application to another. XML was chosen as a
44 configuration file format because it provides a format which is
45 easy for external agents to edit while retaining the correct
48 Font configuration is separate from font matching; applications
49 needing to do their own matching can access the available fonts
50 from the library and perform private matching. The intent is to
51 permit applications to pick and choose appropriate
52 functionality from the library instead of forcing them to
53 choose between this library and a private configuration
54 mechanism. The hope is that this will ensure that configuration
55 of fonts for all applications can be centralized in one place.
56 Centralizing font configuration will simplify and regularize
57 font installation and customization.
61 While font patterns may contain essentially any properties,
62 there are some well known properties with associated types.
63 Fontconfig uses some of these properties for font matching and
64 font completion. Others are provided as a convenience for the
65 applications' rendering mechanism.
66 Property Type Description
67 --------------------------------------------------------------
68 family String Font family names
69 familylang String Languages corresponding to each family
70 style String Font style. Overrides weight and slant
71 stylelang String Languages corresponding to each style
72 fullname String Font full names (often includes style)
73 fullnamelang String Languages corresponding to each fullname
74 slant Int Italic, oblique or roman
75 weight Int Light, medium, demibold, bold or black
76 size Double Point size
77 width Int Condensed, normal or expanded
78 aspect Double Stretches glyphs horizontally before hinting
79 pixelsize Double Pixel size
80 spacing Int Proportional, dual-width, monospace or charcel
82 foundry String Font foundry name
83 antialias Bool Whether glyphs can be antialiased
84 hinting Bool Whether the rasterizer should use hinting
85 hintstyle Int Automatic hinting style
86 verticallayout Bool Use vertical layout
87 autohint Bool Use autohinter instead of normal hinter
88 globaladvance Bool Use font global advance data (deprecated)
89 file String The filename holding the font
90 index Int The index of the font within the file
91 ftface FT_Face Use the specified FreeType face object
92 rasterizer String Which rasterizer is in use (deprecated)
93 outline Bool Whether the glyphs are outlines
94 scalable Bool Whether glyphs can be scaled
95 color Bool Whether any glyphs have color
96 scale Double Scale factor for point->pixel conversions (dep
98 dpi Double Target dots per inch
99 rgba Int unknown, rgb, bgr, vrgb, vbgr,
100 none - subpixel geometry
101 lcdfilter Int Type of LCD filter
102 minspace Bool Eliminate leading from line spacing
103 charset CharSet Unicode chars encoded by the font
104 lang String List of RFC-3066-style languages this
106 fontversion Int Version number of the font
107 capability String List of layout capabilities in the font
108 fontformat String String name of the font format
109 embolden Bool Rasterizer should synthetically embolden the f
111 embeddedbitmap Bool Use the embedded bitmap instead of the outline
112 decorative Bool Whether the style is a decorative variant
113 fontfeatures String List of the feature tags in OpenType to be ena
115 namelang String Language name to be used for the default value
117 familylang, stylelang, and fullnamelang
118 prgname String String Name of the running program
119 postscriptname String Font family name in PostScript
120 fonthashint Bool Whether the font has hinting
121 order Int Order number of the font
125 Fontconfig performs matching by measuring the distance from a
126 provided pattern to all of the available fonts in the system.
127 The closest matching font is selected. This ensures that a font
128 will always be returned, but doesn't ensure that it is anything
129 like the requested pattern.
131 Font matching starts with an application constructed pattern.
132 The desired attributes of the resulting font are collected
133 together in a pattern. Each property of the pattern can contain
134 one or more values; these are listed in priority order; matches
135 earlier in the list are considered "closer" than matches later
138 The initial pattern is modified by applying the list of editing
139 instructions specific to patterns found in the configuration;
140 each consists of a match predicate and a set of editing
141 operations. They are executed in the order they appeared in the
142 configuration. Each match causes the associated sequence of
143 editing operations to be applied.
145 After the pattern has been edited, a sequence of default
146 substitutions are performed to canonicalize the set of
147 available properties; this avoids the need for the lower layers
148 to constantly provide default values for various font
149 properties during rendering.
151 The canonical font pattern is finally matched against all
152 available fonts. The distance from the pattern to the font is
153 measured for each of several properties: foundry, charset,
154 family, lang, spacing, pixelsize, style, slant, weight,
155 antialias, rasterizer and outline. This list is in priority
156 order -- results of comparing earlier elements of this list
157 weigh more heavily than later elements.
159 There is one special case to this rule; family names are split
160 into two bindings; strong and weak. Strong family names are
161 given greater precedence in the match than lang elements while
162 weak family names are given lower precedence than lang
163 elements. This permits the document language to drive font
164 selection when any document specified font is unavailable.
166 The pattern representing that font is augmented to include any
167 properties found in the pattern but not found in the font
168 itself; this permits the application to pass rendering
169 instructions or any other data through the matching system.
170 Finally, the list of editing instructions specific to fonts
171 found in the configuration are applied to the pattern. This
172 modified pattern is returned to the application.
174 The return value contains sufficient information to locate and
175 rasterize the font, including the file name, pixel size and
176 other rendering data. As none of the information involved
177 pertains to the FreeType library, applications are free to use
178 any rasterization engine or even to take the identified font
179 file and access it directly.
181 The match/edit sequences in the configuration are performed in
182 two passes because there are essentially two different
183 operations necessary -- the first is to modify how fonts are
184 selected; aliasing families and adding suitable defaults. The
185 second is to modify how the selected fonts are rasterized.
186 Those must apply to the selected font, not the original pattern
187 as false matches will often occur.
191 Fontconfig provides a textual representation for patterns that
192 the library can both accept and generate. The representation is
193 in three parts, first a list of family names, second a list of
194 point sizes and finally a list of additional properties:
195 <families>-<point sizes>:<name1>=<values1>:<name2>=<values2>...
197 Values in a list are separated with commas. The name needn't
198 include either families or point sizes; they can be elided. In
199 addition, there are symbolic constants that simultaneously
200 indicate both a name and a value. Here are some examples:
202 ----------------------------------------------------------
203 Times-12 12 point Times Roman
204 Times-12:bold 12 point Times Bold
205 Courier:italic Courier Italic in the default size
206 Monospace:matrix=1 .1 0 1 The users preferred monospace font
207 with artificial obliquing
209 The '\', '-', ':' and ',' characters in family names must be
210 preceded by a '\' character to avoid having them
211 misinterpreted. Similarly, values containing '\', '=', '_', ':'
212 and ',' must also have them preceded by a '\' character. The
213 '\' characters are stripped out of the family name and values
214 as the font name is read.
216 Debugging Applications
218 To help diagnose font and applications problems, fontconfig is
219 built with a large amount of internal debugging left enabled.
220 It is controlled by means of the FC_DEBUG environment variable.
221 The value of this variable is interpreted as a number, and each
222 bit within that value controls different debugging messages.
224 ---------------------------------------------------------
225 MATCH 1 Brief information about font matching
226 MATCHV 2 Extensive font matching information
227 EDIT 4 Monitor match/test/edit execution
228 FONTSET 8 Track loading of font information at startup
229 CACHE 16 Watch cache files being written
230 CACHEV 32 Extensive cache file writing information
231 PARSE 64 (no longer in use)
232 SCAN 128 Watch font files being scanned to build caches
233 SCANV 256 Verbose font file scanning information
234 MEMORY 512 Monitor fontconfig memory usage
235 CONFIG 1024 Monitor which config files are loaded
236 LANGSET 2048 Dump char sets used to construct lang values
237 MATCH2 4096 Display font-matching transformation in patterns
239 Add the value of the desired debug levels together and assign
240 that (in base 10) to the FC_DEBUG environment variable before
241 running the application. Output from these statements is sent
246 Each font in the database contains a list of languages it
247 supports. This is computed by comparing the Unicode coverage of
248 the font with the orthography of each language. Languages are
249 tagged using an RFC-3066 compatible naming and occur in two
250 parts -- the ISO 639 language tag followed a hyphen and then by
251 the ISO 3166 country code. The hyphen and country code may be
254 Fontconfig has orthographies for several languages built into
255 the library. No provision has been made for adding new ones
256 aside from rebuilding the library. It currently supports 122 of
257 the 139 languages named in ISO 639-1, 141 of the languages with
258 two-letter codes from ISO 639-2 and another 30 languages with
259 only three-letter codes. Languages with both two and three
260 letter codes are provided with only the two letter code.
262 For languages used in multiple territories with radically
263 different character sets, fontconfig includes per-territory
264 orthographies. This includes Azerbaijani, Kurdish, Pashto,
265 Tigrinya and Chinese.
267 Configuration File Format
269 Configuration files for fontconfig are stored in XML format;
270 this format makes external configuration tools easier to write
271 and ensures that they will generate syntactically correct
272 configuration files. As XML files are plain text, they can also
273 be manipulated by the expert user using a text editor.
275 The fontconfig document type definition resides in the external
276 entity "fonts.dtd"; this is normally stored in the default font
277 configuration directory (/etc/fonts). Each configuration file
278 should contain the following structure:
279 <?xml version="1.0"?>
280 <!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
287 This is the top level element for a font configuration and can
288 contain <dir>, <cachedir>, <include>, <match> and <alias>
289 elements in any order.
291 <dir prefix="default" salt="">
293 This element contains a directory name which will be scanned
294 for font files to include in the set of available fonts.
296 If 'prefix' is set to "default" or "cwd", the current working
297 directory will be added as the path prefix prior to the value.
298 If 'prefix' is set to "xdg", the value in the XDG_DATA_HOME
299 environment variable will be added as the path prefix. please
300 see XDG Base Directory Specification for more details. If
301 'prefix' is set to "relative", the path of current file will be
302 added prior to the value.
304 'salt' property affects to determine cache filename. this is
305 useful for example when having different fonts sets on same
306 path at container and share fonts from host on different font
309 <cachedir prefix="default">
311 This element contains a directory name that is supposed to be
312 stored or read the cache of font information. If multiple
313 elements are specified in the configuration file, the directory
314 that can be accessed first in the list will be used to store
315 the cache files. If it starts with '~', it refers to a
316 directory in the users home directory. If 'prefix' is set to
317 "xdg", the value in the XDG_CACHE_HOME environment variable
318 will be added as the path prefix. please see XDG Base Directory
319 Specification for more details. The default directory is
320 ``$XDG_CACHE_HOME/fontconfig'' and it contains the cache files
321 named ``<hash value>-<architecture>.cache-<version>'', where
322 <version> is the fontconfig cache file version number
325 <include ignore_missing="no" prefix="default">
327 This element contains the name of an additional configuration
328 file or directory. If a directory, every file within that
329 directory starting with an ASCII digit (U+0030 - U+0039) and
330 ending with the string ``.conf'' will be processed in sorted
331 order. When the XML datatype is traversed by FcConfigParse, the
332 contents of the file(s) will also be incorporated into the
333 configuration by passing the filename(s) to
334 FcConfigLoadAndParse. If 'ignore_missing' is set to "yes"
335 instead of the default "no", a missing file or directory will
336 elicit no warning message from the library. If 'prefix' is set
337 to "xdg", the value in the XDG_CONFIG_HOME environment variable
338 will be added as the path prefix. please see XDG Base Directory
339 Specification for more details.
343 This element provides a place to consolidate additional
344 configuration information. <config> can contain <blank> and
345 <rescan> elements in any order.
347 <description domain="fontconfig-conf">
349 This element is supposed to hold strings which describe what a
350 config is used for. This string can be translated through
351 gettext. 'domain' needs to be set the proper name to apply
352 then. fontconfig will tries to retrieve translations with
353 'domain' from gettext.
357 Fonts often include "broken" glyphs which appear in the
358 encoding but are drawn as blanks on the screen. Within the
359 <blank> element, place each Unicode characters which is
360 supposed to be blank in an <int> element. Characters outside of
361 this set which are drawn as blank will be elided from the set
362 of characters supported by the font.
364 <remap-dir prefix="default" as-path="" salt="">
366 This element contains a directory name where will be mapped as
367 the path 'as-path' in cached information. This is useful if the
368 directory name is an alias (via a bind mount or symlink) to
369 another directory in the system for which cached font
370 information is likely to exist.
372 'salt' property affects to determine cache filename as same as
377 This element removes all of fonts directories where added by
378 <dir> elements. This is useful to override fonts directories
379 from system to own fonts directories only.
383 The <rescan> element holds an <int> element which indicates the
384 default interval between automatic checks for font
385 configuration changes. Fontconfig will validate all of the
386 configuration files and directories and automatically rebuild
387 the internal datastructures when this interval passes.
391 This element is used to black/white list fonts from being
392 listed or matched against. It holds acceptfont and rejectfont
397 Fonts matched by an acceptfont element are "whitelisted"; such
398 fonts are explicitly included in the set of fonts used to
399 resolve list and match requests; including them in this list
400 protects them from being "blacklisted" by a rejectfont element.
401 Acceptfont elements include glob and pattern elements which are
406 Fonts matched by an rejectfont element are "blacklisted"; such
407 fonts are excluded from the set of fonts used to resolve list
408 and match requests as if they didn't exist in the system.
409 Rejectfont elements include glob and pattern elements which are
414 Glob elements hold shell-style filename matching patterns
415 (including ? and *) which match fonts based on their complete
416 pathnames. This can be used to exclude a set of directories
417 (/usr/share/fonts/uglyfont*), or particular font file types
418 (*.pcf.gz), but the latter mechanism relies rather heavily on
419 filenaming conventions which can't be relied upon. Note that
420 globs only apply to directories, not to individual fonts.
424 Pattern elements perform list-style matching on incoming fonts;
425 that is, they hold a list of elements and associated values. If
426 all of those elements have a matching value, then the pattern
427 matches the font. This can be used to select fonts based on
428 attributes of the font (scalable, bold, etc), which is a more
429 reliable mechanism than using file extensions. Pattern elements
430 include patelt elements.
432 <patelt name="property">
434 Patelt elements hold a single pattern element and list of
435 values. They must have a 'name' attribute which indicates the
436 pattern element name. Patelt elements include int, double,
437 string, matrix, bool, charset and const elements.
439 <match target="pattern">
441 This element holds first a (possibly empty) list of <test>
442 elements and then a (possibly empty) list of <edit> elements.
443 Patterns which match all of the tests are subjected to all the
444 edits. If 'target' is set to "font" instead of the default
445 "pattern", then this element applies to the font name resulting
446 from a match rather than a font pattern to be matched. If
447 'target' is set to "scan", then this element applies when the
448 font is scanned to build the fontconfig database.
450 <test qual="any" name="property" target="default" compare="eq">
452 This element contains a single value which is compared with the
453 target ('pattern', 'font', 'scan' or 'default') property
454 "property" (substitute any of the property names seen above).
455 'compare' can be one of "eq", "not_eq", "less", "less_eq",
456 "more", "more_eq", "contains" or "not_contains". 'qual' may
457 either be the default, "any", in which case the match succeeds
458 if any value associated with the property matches the test
459 value, or "all", in which case all of the values associated
460 with the property must match the test value. 'ignore-blanks'
461 takes a boolean value. if 'ignore-blanks' is set "true", any
462 blanks in the string will be ignored on its comparison. this
463 takes effects only when compare="eq" or compare="not_eq". When
464 used in a <match target="font"> element, the target= attribute
465 in the <test> element selects between matching the original
466 pattern or the font. "default" selects whichever target the
467 outer <match> element has selected.
469 <edit name="property" mode="assign" binding="weak">
471 This element contains a list of expression elements (any of the
472 value or operator elements). The expression elements are
473 evaluated at run-time and modify the property "property". The
474 modification depends on whether "property" was matched by one
475 of the associated <test> elements, if so, the modification may
476 affect the first matched value. Any values inserted into the
477 property are given the indicated binding ("strong", "weak" or
478 "same") with "same" binding using the value from the matched
479 pattern element. 'mode' is one of:
480 Mode With Match Without Match
481 ---------------------------------------------------------------------
482 "assign" Replace matching value Replace all values
483 "assign_replace" Replace all values Replace all values
484 "prepend" Insert before matching Insert at head of list
485 "prepend_first" Insert at head of list Insert at head of list
486 "append" Append after matching Append at end of list
487 "append_last" Append at end of list Append at end of list
488 "delete" Delete matching value Delete all values
489 "delete_all" Delete all values Delete all values
491 <int>, <double>, <string>, <bool>
493 These elements hold a single value of the indicated type.
494 <bool> elements hold either true or false. An important
495 limitation exists in the parsing of floating point numbers --
496 fontconfig requires that the mantissa start with a digit, not a
497 decimal point, so insert a leading zero for purely fractional
498 values (e.g. use 0.5 instead of .5 and -0.5 instead of -.5).
502 This element holds four numerical expressions of an affine
503 transformation. At their simplest these will be four <double>
504 elements but they can also be more involved expressions.
508 This element holds the two <int> elements of a range
513 This element holds at least one <int> element of an Unicode
518 This element holds at least one <string> element of a
519 RFC-3066-style languages or more.
523 Holds a property name. Evaluates to the first value from the
524 property of the pattern. If the 'target' attribute is not
525 present, it will default to 'default', in which case the
526 property is returned from the font pattern during a
527 target="font" match, and to the pattern during a
528 target="pattern" match. The attribute can also take the values
529 'font' or 'pattern' to explicitly choose which pattern to use.
530 It is an error to use a target of 'font' in a match that has
535 Holds the name of a constant; these are always integers and
536 serve as symbolic names for common font values:
537 Constant Property Value
538 -------------------------------------
558 ultracondensed width 50
559 extracondensed width 63
561 semicondensed width 87
563 semiexpanded width 113
565 extraexpanded width 150
566 ultraexpanded width 200
567 proportional spacing 0
578 lcddefault lcdfilter 1
580 lcdlegacy lcdfilter 3
582 hintslight hintstyle 1
583 hintmedium hintstyle 2
586 <or>, <and>, <plus>, <minus>, <times>, <divide>
588 These elements perform the specified operation on a list of
589 expression elements. <or> and <and> are boolean, not bitwise.
591 <eq>, <not_eq>, <less>, <less_eq>, <more>, <more_eq>, <contains>,
594 These elements compare two values, producing a boolean result.
598 Inverts the boolean sense of its one expression element
602 This element takes three expression elements; if the value of
603 the first is true, it produces the value of the second,
604 otherwise it produces the value of the third.
608 Alias elements provide a shorthand notation for the set of
609 common match operations needed to substitute one font family
610 for another. They contain a <family> element followed by
611 optional <prefer>, <accept> and <default> elements. Fonts
612 matching the <family> element are edited to prepend the list of
613 <prefer>ed families before the matching <family>, append the
614 <accept>able families after the matching <family> and append
615 the <default> families to the end of the family list.
619 Holds a single font family name
621 <prefer>, <accept>, <default>
623 These hold a list of <family> elements to be used by the
626 EXAMPLE CONFIGURATION FILE
628 System configuration file
630 This is an example of a system-wide configuration file
631 <?xml version="1.0"?>
632 <!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
633 <!-- /etc/fonts/fonts.conf file to configure system font access -->
636 Find fonts in these directories
638 <dir>/usr/share/fonts</dir>
639 <dir>/usr/X11R6/lib/X11/fonts</dir>
642 Accept deprecated 'mono' alias, replacing it with 'monospace'
644 <match target="pattern">
645 <test qual="any" name="family"><string>mono</string></test>
646 <edit name="family" mode="assign"><string>monospace</string></ed
651 Names not including any well known alias are given 'sans-serif'
653 <match target="pattern">
654 <test qual="all" name="family" compare="not_eq"><string>sans-ser
656 <test qual="all" name="family" compare="not_eq"><string>serif</s
658 <test qual="all" name="family" compare="not_eq"><string>monospac
660 <edit name="family" mode="append_last"><string>sans-serif</strin
665 Load per-user customization file, but don't complain
668 <include ignore_missing="yes" prefix="xdg">fontconfig/fonts.conf</includ
672 Load local customization files, but don't complain
675 <include ignore_missing="yes">conf.d</include>
676 <include ignore_missing="yes">local.conf</include>
679 Alias well known font names to available TrueType fonts.
680 These substitute TrueType faces for similar Type1
681 faces to improve screen appearance.
684 <family>Times</family>
685 <prefer><family>Times New Roman</family></prefer>
686 <default><family>serif</family></default>
689 <family>Helvetica</family>
690 <prefer><family>Arial</family></prefer>
691 <default><family>sans</family></default>
694 <family>Courier</family>
695 <prefer><family>Courier New</family></prefer>
696 <default><family>monospace</family></default>
700 Provide required aliases for standard names
701 Do these after the users configuration file so that
702 any aliases there are used preferentially
705 <family>serif</family>
706 <prefer><family>Times New Roman</family></prefer>
709 <family>sans</family>
710 <prefer><family>Arial</family></prefer>
713 <family>monospace</family>
714 <prefer><family>Andale Mono</family></prefer>
718 The example of the requirements of OR operator;
719 If the 'family' contains 'Courier New' OR 'Courier'
720 add 'monospace' as the alternative
722 <match target="pattern">
723 <test name="family" compare="eq">
724 <string>Courier New</string>
726 <edit name="family" mode="prepend">
727 <string>monospace</string>
730 <match target="pattern">
731 <test name="family" compare="eq">
732 <string>Courier</string>
734 <edit name="family" mode="prepend">
735 <string>monospace</string>
741 User configuration file
743 This is an example of a per-user configuration file that lives
744 in $XDG_CONFIG_HOME/fontconfig/fonts.conf
745 <?xml version="1.0"?>
746 <!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
747 <!-- $XDG_CONFIG_HOME/fontconfig/fonts.conf for per-user font configurat
752 Private font directory
754 <dir prefix="xdg">fonts</dir>
757 use rgb sub-pixel ordering to improve glyph appearance on
758 LCD screens. Changes affecting rendering, but not matching
759 should always use target="font".
761 <match target="font">
762 <edit name="rgba" mode="assign"><const>rgb</const></edit>
765 use WenQuanYi Zen Hei font when serif is requested for Chinese
769 If you don't want to use WenQuanYi Zen Hei font for zh-t
771 you can use zh-cn instead of zh.
772 Please note, even if you set zh-cn, it still matches zh.
773 if you don't like it, you can use compare="eq"
774 instead of compare="contains".
776 <test name="lang" compare="contains">
780 <string>serif</string>
782 <edit name="family" mode="prepend">
783 <string>WenQuanYi Zen Hei</string>
787 use VL Gothic font when sans-serif is requested for Japanese
790 <test name="lang" compare="contains">
794 <string>sans-serif</string>
796 <edit name="family" mode="prepend">
797 <string>VL Gothic</string>
804 fonts.conf contains configuration information for the
805 fontconfig library consisting of directories to look at for
806 font information as well as instructions on editing program
807 specified font patterns before attempting to match the
808 available fonts. It is in XML format.
810 conf.d is the conventional name for a directory of additional
811 configuration files managed by external applications or the
812 local administrator. The filenames starting with decimal digits
813 are sorted in lexicographic order and used as additional
814 configuration files. All of these files are in XML format. The
815 master fonts.conf file references this directory in an
818 fonts.dtd is a DTD that describes the format of the
821 $XDG_CONFIG_HOME/fontconfig/conf.d and ~/.fonts.conf.d is the
822 conventional name for a per-user directory of (typically
823 auto-generated) configuration files, although the actual
824 location is specified in the global fonts.conf file. please
825 note that ~/.fonts.conf.d is deprecated now. it will not be
826 read by default in the future version.
828 $XDG_CONFIG_HOME/fontconfig/fonts.conf and ~/.fonts.conf is the
829 conventional location for per-user font configuration, although
830 the actual location is specified in the global fonts.conf file.
831 please note that ~/.fonts.conf is deprecated now. it will not
832 be read by default in the future version.
834 $XDG_CACHE_HOME/fontconfig/*.cache-* and
835 ~/.fontconfig/*.cache-* is the conventional repository of font
836 information that isn't found in the per-directory caches. This
837 file is automatically maintained by fontconfig. please note
838 that ~/.fontconfig/*.cache-* is deprecated now. it will not be
839 read by default in the future version.
841 Environment variables
843 FONTCONFIG_FILE is used to override the default configuration
846 FONTCONFIG_PATH is used to override the default configuration
849 FONTCONFIG_SYSROOT is used to set a default sysroot directory.
851 FC_DEBUG is used to output the detailed debugging messages. see
852 Debugging Applications section for more details.
854 FC_DBG_MATCH_FILTER is used to filter out the patterns. this
855 takes a comma-separated list of object names and effects only
856 when FC_DEBUG has MATCH2. see Debugging Applications section
859 FC_LANG is used to specify the default language as the weak
860 binding in the query. if this isn't set, the default language
861 will be determined from current locale.
863 FONTCONFIG_USE_MMAP is used to control the use of mmap(2) for
864 the cache files if available. this take a boolean value.
865 fontconfig will checks if the cache files are stored on the
866 filesystem that is safe to use mmap(2). explicitly setting this
867 environment variable will causes skipping this check and
868 enforce to use or not use mmap(2) anyway.
870 SOURCE_DATE_EPOCH is used to ensure fc-cache(1) generates files
871 in a deterministic manner in order to support reproducible
872 builds. When set to a numeric representation of UNIX timestamp,
873 fontconfig will prefer this value over using the modification
874 timestamps of the input files in order to identify which cache
875 files require regeneration. If SOURCE_DATE_EPOCH is not set (or
876 is newer than the mtime of the directory), the existing
877 behaviour is unchanged.
881 fc-cat(1), fc-cache(1), fc-list(1), fc-match(1), fc-query(1),
886 Fontconfig version 2.14.2