The compiler on my newer Linux box warns about a lot of unchecked return
values, so I'm starting to clean this up.  Attached are a couple patches
that make headway in this area:

I hope the first in uncontroversial, simple improvements, and I'm going
to check it in.

The second is specific to checking the return value of pipe(), and there
is some cleanup there that I'm not too sure about yet.  For instance,
I'm curious if my disabling of the WC_SUBLIST_COPROC bit on failure is a
good idea or not.  There's also a couple FIXME spots where I wasn't sure
how to return an error which I will look at this again when I have more
time (but feel free to chime in if you have some suggestions).  This
patch will not be committed as-is.

Finally, I haven't yet patched the various read()/write()/fwrite() calls
that are not checking their return values.  I'm thinking about adding a
helper function for each one that would iterate over its buffer as
needed to handle partial read/write or a signal-interrupt.

..wayne..