Convert to C/C++?

Jorgen Grahn grahn+nntp at snipabacken.dyndns.org
Tue Jun 19 10:35:12 EDT 2007


On Thu, 14 Jun 2007 13:16:42 -0700, SpreadTooThin <bjobrien62 at gmail.com> wrote:
> I am wondering if someone who knows the implemention of python's time
> could help converting this to c/c++....
>
> 		nanoseconds = int(time.time() * 1e9)

[straightforward non-time arithmetic snipped]

>
> vs unix gettimeofday....
>
> int gettimeofday(struct timeval *tp, struct timezone *tzp);
>
> struct timeval {
>    long tv_sec;         /* seconds since Jan. 1, 1970 */
>    long tv_usec;        /* and microseconds */
> };

Quite simply, time.time() corresponds to tv_sec + tv_usec/1e6,
modulo any rounding and numerical errors introduced by the
floating-point format used.

> struct timezone {
>    int tz_minuteswest; /* of Greenwich */
>    int tz_dsttime;     /* type of dst correction to apply */
> };

The struct timezone is not set by Linux/glibc gettimeofday(), so
you can happily ignore it. You only want UTC time anyway.

/Jorgen

-- 
  // Jorgen Grahn <grahn@        Ph'nglui mglw'nafh Cthulhu
\X/     snipabacken.dyndns.org>  R'lyeh wgah'nagl fhtagn!



More information about the Python-list mailing list