id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
7042	Avoiding time_point and duration dependency on time.h and CLOCK_REALTIME	1czajnik@…	viboes	"Hello,

The file chrono/config.hpp enforces that time.h defines CLOCK_REALTIME:
{{{
# if defined( BOOST_CHRONO_POSIX_API )
#   define BOOST_CHRONO_HAS_PROCESS_CLOCKS
#   include <time.h>  //to check for CLOCK_REALTIME and CLOCK_MONOTONIC and _POSIX_THREAD_CPUTIME
#   if defined(CLOCK_REALTIME)
#     if defined(CLOCK_MONOTONIC)
#        define BOOST_CHRONO_HAS_CLOCK_STEADY
#     endif
#   else
#     error <time.h> does not supply CLOCK_REALTIME
#   endif
...
# endif
}}}

It seems that files: chrono/duration.hpp and chrono/time_point.hpp don't need to depend on <time.h> or CLOCK_REALTIME. 
If a compiler provides a <time.h>, which doesn't define CLOCK_REALTIME, or even doesn't provide <time.h>, it would be nice to still be able to use chrono/duration.hpp or chrono/time_point.hpp.

Regards,
Kris"	Feature Requests	closed	Boost 1.51.0	chrono	Boost Development Trunk	Problem	fixed