vxWorks POSIX quirks for date_time

[Dustin Spicuzza <dustin@…>]

vxWorks is almost a unix-like platform, that supports the POSIX realtime extensions and a lot of POSIX stuff.. but its weird.

It apparently doesn't support gettimeofday. I modified microsec_time_clock to support a situation where gettimeofday isn't available but clock_gettime is.

vxWorks has localtime_r, but it is defined as "extern int localtime_r (const time_t *_tod, struct tm *_result);"... so it needs some hand holding to work correctly. same with gmtime_r

Of course, this patch also requires the user to setup a config that defines BOOST_HAS_CLOCK_GETTIME, but I'm going to submit a separate patch for vxWorks platform config

[Dustin Spicuzza <dustin@…>]

This is a pretty trivial patch, do you think you could take a look at it at some point?

[viboes]

I see a possible problem with this patch.

Adding a new config macro need to provide a test also. I gues we can change

        result = localtime_r(t, result); 

by

        (void)localtime_r(t, result); 

without too much trouble