Reference

XGetFontProperty(3x) on Linux

The text 6f7dfa87ad9f, as Debian 2.2 (Potato), Debian 2.1 (Slink), Debian 2.0 (Hamm), Debian 1.3 (Bo) shipped it.

load or unload fonts and font metric structures

XGetFontProperty(3x) on Linux now