Serialization, readers, writers, message queues and file descriptors

I looked at my serialization code, decided it was wrong, started rewriting it. So, first I rewrote it with abstract readers and writers. Great, to do that the right way I would need multiple parameter type classes; a reader r is some abstract construct reading things of type t. Solved that problem, in my head at least, it ain't difficult in my setting. Decided the multiple parameter type classes are for later, restricted the IO type to word. But then again, I already interface with C, and actually, file descriptors are then a better option than implementing heavy-weight reader and writer interfaces. Looked at file descriptors if I could use those as message queues for IPC, and behold, supported in Linux, not Posix, so not portable? What now?

Oh god, mmap for IPC?