X logical font description

X logical font description (XLFD) is a font standard used by the X Window System. Modern X software typically relies on the newer Fontconfig system instead, but XLFDs are still supported in current X window implementations for compatibility with legacy software.

XLFD is intended to support:

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

The following sample is for a 75-dpi, 12-point, Charter font:

(which also tells the font source that the client is interested only in characters 65, 70, and 80-90.)

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