安装的程序: addftinfo,
afmtodit, eqn, eqn2graph, geqn (链接到 eqn), grn, grodvi,
groff, groffer, grog, grolbp, grolj4, grops, grotty, gtbl (链接到 tbl), hpftodit, indxbib, lkbib, lookbib, mmroff, neqn,
nroff, pfbtops, pic, pic2graph, post-grohtml, pre-grohtml,
refer, soelim, tbl, tfmtodit, troff, zsoelim (链接到 soelim)