time_get - Acquire the current time.
#include <zircon/syscalls.h>
zx_time_t zx_time_get(uint32_t clock_id)
zx_time_get() returns the current time of clock_id, or 0 if clock_id is invalid.
ZX_CLOCK_MONOTONIC number of nanoseconds since the system was powered on.
ZX_CLOCK_UTC number of wall clock nanoseconds since the Unix epoch (midnight on January 1 1970) in UTC
ZX_CLOCK_THREAD number of nanoseconds the current thread has been running for.
On success, zx_time_get() returns the current time according to the given clock ID.
On error, zx_time_get() currently returns 0.