Any change of rsync using threads instead of fork?

[Jamie Lokier]

On a typical embedded Linux device, with no MMU, there is no fork() or
it returns ENOSYS.

The nearest replacements are vfork() (which is only useful before
exec*()), or to create threads with pthread_create().

rsync would be a very useful program on such devices, and I was a bit
disappointed to build it, only to find the compile went fine but it
failed at runtime due to ENOSYS.

Is there any likelihood of changing the rsync code to use threads
instead of processes?  Would it be a lot of work?  I notice it has
been attempted before, but the attempt seems to have been abandoned.

Thanks,
-- Jamie