When running on X, Emacs creates a standard fontset automatically according to the value
standard-fontset-spec. This fontset’s name is
or just ‘
fontset-standard’ for short.
On GNUstep and macOS, the standard fontset is created using the value of
ns-standard-fontset-spec, and on MS Windows it is
created using the value of
Bold, italic, and bold-italic variants of the standard fontset are
created automatically. Their names have ‘
bold’ instead of
medium’, or ‘
i’ instead of ‘
r’, or both.
Emacs generates a fontset automatically, based on any default
ASCII font that you specify with the ‘
Font’ resource or
-fn’ argument, or the default font that Emacs found when it
started. This is the startup fontset and its name is
fontset-startup. Emacs generates this fontset by replacing the
charset_registry field with ‘
fontset’, and replacing the
charset_encoding field with ‘
startup’, then using the
resulting string to specify a fontset.
For instance, if you start Emacs with a font of this form,
emacs -fn "*courier-medium-r-normal--14-140-*-iso8859-1"
Emacs generates the following fontset and uses it for the initial X window frame:
The startup fontset will use the font that you specify, or a variant
with a different registry and encoding, for all the characters that
are supported by that font, and fallback on ‘
With the X resource ‘
Emacs.Font’, you can specify a fontset name
just like an actual font name. But be careful not to specify a fontset
name in a wildcard resource like ‘
specification matches various other resources, such as for menus, and
menus cannot handle fontsets. See X Resources.
You can specify additional fontsets using X resources named
n is an integer starting from 0.
The resource value should have this form:
fontpattern should have the form of a standard X font name
(see the previous fontset-startup example), except for the last two
fields. They should have the form ‘
Each fontset has two names, one long and one short. The long name
fontpattern. The short name is ‘
the last 2 fields of the long name (e.g., ‘
the fontset automatically created at startup). You can refer to the
fontset by either name.
The construct ‘
charset:font’ specifies which font to
use (in this fontset) for one particular character set. Here,
charset is the name of a character set, and
font is the
font to use for that character set. You can use this construct any
number of times in defining one fontset.
For the other character sets, Emacs chooses a font based on
fontpattern. It replaces ‘
fontset-alias’ with values
that describe the character set. For the ASCII character font,
fontset-alias’ is replaced with ‘
In addition, when several consecutive fields are wildcards, Emacs collapses them into a single wildcard. This is to prevent use of auto-scaled fonts. Fonts made by scaling larger fonts are not usable for editing, and scaling a smaller font is also not useful, because it is better to use the smaller font in its own size, which is what Emacs does.
fontpattern is this,
the font specification for ASCII characters would be this:
and the font specification for Chinese GB2312 characters would be this:
You may not have any Chinese font matching the above font
specification. Most X distributions include only Chinese fonts that
song ti’ or ‘
fangsong ti’ in the
family field. In
such a case, ‘
Fontset-n’ can be specified as:
Emacs.Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24,\ chinese-gb2312:-*-*-medium-r-normal-*-24-*-gb2312*-*
Then, the font specifications for all but Chinese GB2312 characters have
fixed’ in the
family field, and the font specification for
Chinese GB2312 characters has a wild card ‘
*’ in the
The function that processes the fontset resource value to create the
fontset is called
create-fontset-from-fontset-spec. You can also
call this function explicitly to create a fontset.
See Fonts, for more information about font naming.