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XCreateFontSet(3)               XLIB FUNCTIONS               XCreateFontSet(3)



NAME
       XCreateFontSet, XFreeFontSet - create and free an international text
       drawing font set

SYNTAX
       XFontSet XCreateFontSet(Display *display, char *base_font_name_list,
              char ***missing_charset_list_return, int *miss-
              ing_charset_count_return, char **def_string_return);

       void XFreeFontSet(Display *display, XFontSet font_set);

ARGUMENTS
       display   Specifies the connection to the X server.

       base_font_name_list
                 Specifies the base font names.

       def_string_return
                 Returns the string drawn for missing charsets.

       font_set  Specifies the font set.

       missing_charset_count_return
                 Returns the number of missing charsets.

       missing_charset_list_return
                 Returns the missing charsets.

DESCRIPTION
       The XCreateFontSet function creates a font set for the specified dis-
       play.  The font set is bound to the current locale when XCreateFontSet
       is called.  The font set may be used in subsequent calls to obtain font
       and character information and to image text in the locale of the font
       set.

       The base_font_name_list argument is a list of base font names that Xlib
       uses to load the fonts needed for the locale.  The base font names are
       a comma-separated list.  The string is null-terminated and is assumed
       to be in the Host Portable Character Encoding; otherwise, the result is
       implementation-dependent.  White space immediately on either side of a
       separating comma is ignored.

       Use of XLFD font names permits Xlib to obtain the fonts needed for a
       variety of locales from a single locale-independent base font name.
       The single base font name should name a family of fonts whose members
       are encoded in the various charsets needed by the locales of interest.

       An XLFD base font name can explicitly name a charset needed for the
       locale.  This allows the user to specify an exact font for use with a
       charset required by a locale, fully controlling the font selection.

       If a base font name is not an XLFD name, Xlib will attempt to obtain an
       XLFD name from the font properties for the font.  If this action is
       successful in obtaining an XLFD name, the XBaseFontNameListOfFontSet
       function will return this XLFD name instead of the client-supplied
       name.

       Xlib uses the following algorithm to select the fonts that will be used
       to display text with the XFontSet.

       For each font charset required by the locale, the base font name list
       is searched for the first appearance of one of the following cases that
       names a set of fonts that exist at the server:

       o    The first XLFD-conforming base font name that specifies the
            required charset or a superset of the required charset in its
            CharSetRegistry and CharSetEncoding fields.  The implementation
            may use a base font name whose specified charset is a superset of
            the required charset, for example, an ISO8859-1 font for an ASCII
            charset.

       o    The first set of one or more XLFD-conforming base font names that
            specify one or more charsets that can be remapped to support the
            required charset.  The Xlib implementation may recognize various
            mappings from a required charset to one or more other charsets and
            use the fonts for those charsets.  For example, JIS Roman is ASCII
            with tilde and backslash replaced by yen and overbar; Xlib may
            load an ISO8859-1 font to support this character set if a JIS
            Roman font is not available.

       o    The first XLFD-conforming font name or the first non-XLFD font
            name for which an XLFD font name can be obtained, combined with
            the required charset (replacing the CharSetRegistry and CharSetEn-
            coding fields in the XLFD font name).  As in case 1, the implemen-
            tation may use a charset that is a superset of the required
            charset.

       o    The first font name that can be mapped in some implementation-
            dependent manner to one or more fonts that support imaging text in
            the charset.

       For example, assume that a locale required the charsets:

       ISO8859-1
       JISX0208.1983
       JISX0201.1976
       GB2312-1980.0

       The user could supply a base_font_name_list that explicitly specifies
       the charsets, ensuring that specific fonts are used if they exist.  For
       example:

       "-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240-JISX0208.1983-0,-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120-JISX0201.1976-0,-GB-Fixed-Medium-R-Normal--26-180-100-100-C-240-GB2312-1980.0,-Adobe-Courier-Bold-R-Normal--25-180-75-75-M-150-ISO8859-1"




       Alternatively, the user could supply a base_font_name_list that omits
       the charsets, letting Xlib select font charsets required for the
       locale.  For example:

       "-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240,-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120,-GB-Fixed-Medium-R-Normal--26-180-100-100-C-240,-Adobe-Courier-Bold-R-Normal--25-180-100-100-M-150"




       Alternatively, the user could simply supply a single base font name
       that allows Xlib to select from all available fonts that meet certain
       minimum XLFD property requirements.  For example:

       "-*-*-*-R-Normal--*-180-100-100-*-*"

       If XCreateFontSet is unable to create the font set, either because
       there is insufficient memory or because the current locale is not sup-
       ported, XCreateFontSet returns NULL, missing_charset_list_return is set
       to NULL, and missing_charset_count_return is set to zero.  If fonts
       exist for all of the charsets required by the current locale, XCreate-
       FontSet returns a valid XFontSet, missing_charset_list_return is set to
       NULL, and missing_charset_count_return is set to zero.

       If no font exists for one or more of the required charsets, XCreate-
       FontSet sets missing_charset_list_return to a list of one or more null-
       terminated charset names for which no font exists and sets miss-
       ing_charset_count_return to the number of missing fonts.  The charsets
       are from the list of the required charsets for the encoding of the
       locale and do not include any charsets to which Xlib may be able to
       remap a required charset.

       If no font exists for any of the required charsets or if the locale
       definition in Xlib requires that a font exist for a particular charset
       and a font is not found for that charset, XCreateFontSet returns NULL.
       Otherwise, XCreateFontSet returns a valid XFontSet to font_set.

       When an Xmb/wc drawing or measuring function is called with an XFontSet
       that has missing charsets, some characters in the locale will not be
       drawable.  If def_string_return is non-NULL, XCreateFontSet returns a
       pointer to a string that represents the glyphs that are drawn with this
       XFontSet when the charsets of the available fonts do not include all
       font glyphs required to draw a codepoint.  The string does not neces-
       sarily consist of valid characters in the current locale and is not
       necessarily drawn with the fonts loaded for the font set, but the
       client can draw and measure the default glyphs by including this string
       in a string being drawn or measured with the XFontSet.

       If the string returned to def_string_return is the empty string (""),
       no glyphs are drawn, and the escapement is zero.  The returned string
       is null-terminated.  It is owned by Xlib and should not be modified or
       freed by the client.  It will be freed by a call to XFreeFontSet with
       the associated XFontSet.  Until freed, its contents will not be modi-
       fied by Xlib.

       The client is responsible for constructing an error message from the
       missing charset and default string information and may choose to con-
       tinue operation in the case that some fonts did not exist.

       The returned XFontSet and missing charset list should be freed with
       XFreeFontSet and XFreeStringList, respectively.  The client-supplied
       base_font_name_list may be freed by the client after calling XCreate-
       FontSet.

       The XFreeFontSet function frees the specified font set.  The associated
       base font name list, font name list, XFontStruct list, and XFontSetEx-
       tents, if any, are freed.

SEE ALSO
       XExtentsofFontSet(3X11), XFontsOfFontSet(3X11), XFontSetExtents(3X11)
       Xlib - C Language X Interface



X Version 11                     libX11 1.1.5                XCreateFontSet(3)