Yep. When I designed the scsh syscall interface, I decreed that syscalls never
  return EINTR -- they loop & resume. Want to bail out on an interrupt? Scheme
  has exceptions, so have your signal handler throw out to a handler. EINTR is,
  in my opinion, very bogus. If I missed something important here, OS wizards
  are welcome to set me straight.

YOW!  I have been TELEPORTED to the guile mailinglist!

You are arguably right about EINTR.  The coda vfs code may well need
some help to not return it and instead restart things.

There is still a hard issue about restarting syscalls across signal
delivery and suspending a process, though, and I don't understand that
well enough.