ref: 77f1febdea9d3992cd928b18b51c523fbaa4ae0a 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); }