patch from Charles Levert <charles@comm.polymtl.ca>

this fixes a bug with --backup-dir and -x

added "ignore nonreadable" option (useful for hiding files in public archives)

waitpid()

turns out that when client is talking to a server daemon it never executes
this leg of code.  Oops.  The people who said it made a difference when
they changed the code must have been wrong.

Problem and suggested patch from Dean Scothern dino@cricinfo.com (although
I re-wrote the patch).

from Harry Putnam <reader@newsguy.com>.

don't get interrupted during a sleep.

cause recursive error messages)

rsh relies on stdin being blocking
ssh relies on stdout being non-blocking

what we've done before is to set both stdin and stdout to either
blocking or non-blocking. Now I set stdin to blocking and stdout to
non-blocking. This seems to fix all cases I've tested.

it looks like ssh is willing to accept a non-blocking fd when used as
a transport, this seems to avoid the Solaris socketpair bug