ref: 1461fe5706d6ea7ed7aacca5866a4fdbc682a9fa 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); }