timersub
timersub(&now.ru_utime, &start, &elapsed);
#ifndef timersub
timersub(&finish, start, &diff);
timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
timersub(&next_sendtime, &time_waited, &tv);
timersub(&timeout, &time_waited, &tv);
timersub(&tv, &starttime, &time_waited);
timersub(&tv, &cd->last_recv_time, &tdiff);
timersub(&cur_time, &prev_time, &busy_time);
timersub(&timeout, &now, &delta);
timersub(&timeout, &now, &delta);
timersub(&get, &clear, &get);
timersub(&after.ru_utime, &before.ru_utime, &total);
struct timeval timerstop, timersub;
getmicrotime(&t->timersub);
timevaladd(&t->timersub, &now);
timevalsub(&now, &t->timersub);
timevalsub(&now, &t->timersub);
#ifndef timersub
timersub(&uptime, &src->scrub->pfss_last, &delta_ts);
#ifndef timersub
timersub(&tv, lasttime, &delta);
timersub(&sub_tv, &ref_tv, &res_tv);
timersub(&sub_tv, &ref_tv, &res_tv);
timersub(&sub_tv, &ref_tv, &res_tv);
timersub(&sub_tv, &ref_tv, &res_tv);
timersub(&sub_tv, &ref_tv, &res_tv);
timersub(&end, &now, &delta);
timersub(&now, &end, &delta);
timersub(&new_tv, &old_tv, &tv);
timersub(&new_tv, &old_tv, &tv);
timersub(&timeval, &starttime, &timeval);
timersub(&today, &usec, &yesterday);
timersub(&today, &lp->time, &diff);
timersub(&up->ut_tv, &lp->time, &secs);
timersub(&clock_shift, &ut_timecopy, &clock_shift);
timersub(&lp->time, &clock_shift, &lp->time);
timersub(&end, &(x), &td); \
timersub(&tv1, &tv2, &tv);
timersub(&tv1, &tv2, &tv3);
timersub(&tv1, &tv2, &tv);
timersub(&timelimit, &tv, &tv);