[Rd] pipe(): input to, and output from, a single process

[Greg Minshall]

hi.  i'd like to instantiate sed(1), send it some input, and retrieve
its output, all via pipes (rather than an intermediate file).

my sense from pipe and looking at the sources (sys-unix.c) is that is
not possible.  is that true?  are there any thoughts of providing such a
facility?

cheers, Greg