Plan 9 from Bell Labs’s /usr/web/sources/contrib/steve/root/sys/lib/texmf/metapost/support/charlib/ci
vardef C.ci(expr n) = save p; picture p; p=nullpicture; addto p doublepath makepath pencircle shifted(.5,.5) withpen pencircle scaled.0444; p scaled(.75*fontsize n) enddef;
