The stime() function sets the system's idea of the time and date. The tp argument points to the value of time as measured in seconds from 00:00:00 UTC January 1, 1970.
RETURN VALUES
Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.
ERRORS
The stime() function will fail if:
EINVAL
The tp argument points to an invalid (negative) value.
EPERM
The {PRIV_SYS_TIME} privilege is not asserted in the effective set of the calling process.