Host dependent static arrays

[markehammons]

Certain struct types have sizes that differ based on the host implementation. For example, the posix standard has sockaddr_un, which has a path array of around 100 characters on Linux, but some implementations have arrays as small as 93 characters. We need to provide a mechanism to specify these static arrays on a platform by platform basis and have the structs containing these runtime-dependent static arrays change their shape based on the system running them.