[ Note, I've not chimed in on this thread yet, due to time contraints,
  even though I'm more-or-less responsible for the vfork(2) that's in
  NetBSD-current.  If I have time today, I'll try to post something
  describing my rationale for doing it this way. ]

On Thu, 09 Apr 1998 11:25:47 -0000 (GMT) 
 jiho@postal.c-zone.net wrote:

 > CSRG stated POSIX compliance as a goal for 4.4BSD, and vfork() is not in the
 > POSIX specification.  It's regarded as a BSD quirk.

For what it's worth, XPG4.2 defines the vfork(2) system call, and specifically
states that the address space is shared.  Thus, by having a shared address
space vfork(2), NetBSD has an XPG4.2-compliant vfork(2) system call.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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