ref: f3f4c58027ec7cfeef3e8ce2bb72dfb054a009fd dir: /sys/src/cmd/htmlroff/t15.c/
#include "a.h" /* * 15. Output line numbering. */ void t15init(void) { addreq(L("nm"), r_warn, -1); addreq(L("nn"), r_warn, -1); }