Delay by 1 microsecond in C MIPS Environment -

i'm trying port u8glib (graphics library) mips processor, openwrt router. here's example in arm environment.

as such, 1 of routines must implement is:

delay_micro_seconds(uint32_t us) 

since high resolution unit of time, how can reliably in environment? i've tried following, i'm not sure how validate it:

nanosleep((struct timespec[]){{0, 1000}}, null); 

how can validate approach? if bad approach, how reliably delay 1 microsecond in c?

edit: i've tried this, i'm getting strange output, expect difference between 2 print s 1000*10 iterations = 10,000 , closer 670,000 nanoseconds:

   int main(int argc, char **argv)    {     long res, resb;     struct timespec ts, tsb;     int i;      res = clock_gettime(clock_realtime, &ts);      for(i=0;i<10;i++){             nanosleep((struct timespec[]){{0,1000}}, null);     }      resb = clock_gettime(clock_realtime, &tsb);      if (0 == res) printf("%ld %ld\n", ts.tv_sec, ts.tv_nsec);     else perror("clock_gettime");     if (0 == resb) printf("%ld %ld\n", tsb.tv_sec, tsb.tv_nsec);     else perror("clock_gettime"); //getting 670k delta instead of 10k tv_nsec     return 0;     }  

i assume codes run under linux.

first, using clock_getres(2) find clock's resolution. , then, using clock_nanosleep(2) might make more accurate sleep.

to validate sleep, suggest check elapsed time clock_gettime(2)

res = clock_gettime(clock_realtime, &ts); if (0 == res) printf("%ld %ld\n", ts.tv_sec, ts.tv_nsec); else perror("clock_gettime");  clock_nanosleep(clock_realtime, 0, &delay, null);  res = clock_gettime(clock_realtime, &ts); if (0 == res) printf("%ld %ld\n", ts.tv_sec, ts.tv_nsec); else perror("clock_gettime"); 

also, if necessary, can recompile kernel higher hz configuration. helpful read time(7) man page. especially, the software clock, hz, , jiffies , high-resolution timers sections. though man pages says high-resolution timer not supported under mips architecture googled , mips-linux support hrt apparently.