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Subject: Re: djgpp_terminal
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In DJGPP there is usleep() defined in unistd.h but it's a crap with very coarse granularity, as wtitten in libc.info:
This function pauses the program for USEC microseconds.  Note that,
since `usleep' calls `clock' internally, and the latter has a 55-msec
granularity, any argument less than 55msec will result in a pause of
random length between 0 and 55 msec.

I made my own function udelay() based on uclock() from time.h that is based on sub-microsecond precise timer.

//***************** wait for delay us ***************************************
void udelay(DWord usec)                // based on precise 1us timer uclock(), usable for 10us resolution
{                                      // works under DOS/Win9X/NT but not Win3.x
  volatile uclock_t wait_ticks, t1, t2;
  if (usec==0)                         // pokud je prodleva nulova
    return;                            // tak hned skonci
  wait_ticks=((uclock_t)usec*UCLOCKS_PER_SEC)/1000000LL; // pocet cekanych tiku dle usec
  t1=uclock();                         // precti casovac, pocatecni hodnota
  do {                                 // cekaci smycka
    t2=uclock();                       // precti znova casovac
  } while ((t2-t1)<wait_ticks);        // opakuj dokud je rozdil tiku mensi nez pozadovana hodnota
}