Xlf

It is intended to support:

unique, descriptive font names that support simple pattern matching
multiple font vendors, arbitrary character sets, and encodings
naming and instancing of scalable and polymorphic fonts
transformations and subsetting of fonts
independence of X server and operating or file system implementations
arbitrarily complex font matching or substitution
extensibility

One prominent XFLD convention is to refer to individual fonts including any variations using their unique FontName. It comprises a sequence of fourteen hyphen-prefixed fields:

FOUNDRY
FAMILY_NAME
WEIGHT_NAME
SLANT
SETWIDTH_NAME
ADD_STYLE_NAME
POINT_SIZE
PIXEL_SIZE
RESOLUTION_X
RESOLUTION_Y
SPACING
AVERAGE_WIDTH
CHARSET_REGISTRY
CHARSET_ENCODING

The following sample is for a 75-dpi, 12-point, Charter font:
-Bitstream-Charter-Medium-R-Normal--12-120-75-75-P-68-ISO8859-1

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