Add Todd to the authors; he did way more work on this than I ever did.
merge patch from Greg Lindahl for COW support:
"sys-mmap 0.16 is getting a bit old, here are patches for copy on write and adding the MAP_LOCKED flag."
1 of 2 from https://rt.cpan.org/Ticket/Display.html?id=96043
add MAP_LOCKED patch from Greg Lindahl
https://rt.cpan.org/Ticket/Display.html?id=96043