[PATCH 2/3] posix: Use posix_spawn on popen

[David Newall]

It seems to me that there are still reasonable questions about whether 
to use posix_spawn or vfork ("posix_spawn is a badly designed API").  
For (well over) 30 years, I've understood that vfork was the go-to call 
for a fork/exec scenario, so, what is the technical problem with using 
it for popen and system?  (I'm not asking about vfork's overall 
technical merits, I'm asking exclusively about using it for popen and 
system.)