clock is not portable

[magmaikh]

On Win32 clock reports total elapsed time.
On GNU/Linux clock reports consumed processor time by 
that process, and only reports time on the primary 
thread.  Other threads always return 0, and time spent 
usleep'ing is not counted.

The wording of the C/C++ standard is not without room 
for interpretation, and may even be interpreted to mean 
do whatever you can for clock.

On Linux, and very possibly other *nix's, the function 
gettimeofday (in sys/time.h) should probably be used.

code dump of my linux timer follows:

template<typename T>
struct HPTimer
	{
	i64 Now_us()
		{
		timeval now;
		MKH_THROWONFAILURE(gettimeofday
(&tvnow, 0));
		return i64(now.tv_sec) * 1000000 + 
now.tv_usec;
		}
	T Snap()
		{
		timeval snap;
		//timezone zn;
		MKH_THROWONFAILURE(gettimeofday
(&snap, 0));
		i64 now = i64(snap.tv_sec) * 
1000000 + snap.tv_usec;
		i64 then = i64(prev_snap.tv_sec) * 
1000000 + prev_snap.tv_usec;
		prev_snap = snap;
		return T(now - then) / 1000000;
		}
	protected:
		timeval prev_snap;
	};

[beman_dawes]

Logged In: YES 
user_id=51042

This is what the C++ Committee's library working group calls
a "genetic misfortune". It other words, the implementation
is correct according to the original design, so it won't
change until there is a major revision and the design is
reconsidered.

Timer was one of the original Boost seed libraries. We now
have a much more refined view of portability, and would do
things differently if we were to do a timer-like class
today. Jeff Garland and I have discussed this several times,
but it just isn't bubbling up to the top of the priority list.

Thanks for the report,

--Beman