Question

How can I keep track of time with sub second precision. Can you guys provide me with some ideas and strategies. Also, the pros and cons of each, I am trying to implement this for a hard real-time system using a Linux kernel. The Linux clock() function is not accurate enough since its precision is by seconds.

Answer 1

You can use clock_gettime() to return a struct timespec:

struct timespec {
        time_t   tv_sec;        /* seconds */
        long     tv_nsec;       /* nanoseconds */
};

The actual resolution is typically not anywhere near nanoseconds but should get you into the millisecond range or better.