Issues with clock_gettime(CLOCK_REALTIME, &wait) pre macOS 10.13

[Ken Cunningham]

On 2018-10-23, at 4:23 PM, Chris Jones wrote:
> 
> I see no reason to not just place them directly in the main MacPorts include prefix, i.e. normally /opt/local/include. Placing them anywhere else requires that specific folder to be included as well, which is a complication I dont see the need for. As long as these headers are written properly, they should be completely safe and transparent to use. Either they just include the primary header in cases where it is complete, or they add the missing methods in cases where they are required, but only where they are required. 
> 

I have always liked this idea, and I think we should explore it through to completion. It could ease the burden of supporting older OS versions greatly.

Given that once this "port of headers" is installed it would affect every build whether listed as a dep or not, it would have to be assumed to be installed always, ie a MacPorts default installation.

We would also have to make sure it doesn't interfere with bootstrapping and building compilers like gcc, that have their own mechanism of "fixincludes" that we don't want to mess up.

Ken