clock_gettime() from time.h is not working
I want to get the clock time in milliseconds, and there is a function in time.h called clock_gettime() that looks like it can do this. However, it always remains undefined, and it appears I need to include another POSIX library or something like that to get this clock_gettime() function to work.
Does anyone know how to get this function to work, or if there is an additional library I need for it?
In the time.h file it appears as:
/* Clocks, P1003.1b-1993, p. 263 */
int _EXFUN(clock_settime, (clockid_t clock_id, const struct timespec *tp));
int _EXFUN(clock_gettime, (clockid_t clock_id, struct timespec *tp));