Using pipes example

Do pipes in gforth work at all? (Not Gforth in pipes, that works.)

I'd appreciate a single working example where two gforth instances open 
a pipe and communicate through it (one direction) without getting errors 
like:

s" /tmp/trrr" w/o open-pipe .s <2> 94382312719856 0  ok
sh: 1: /tmp/trrr: not found

or

s" mkfifo /tmp/trrr" system  ok
s" /tmp/trrr" w/o open-pipe .s <2> 94382312605296 0  ok
sh: 1: /tmp/trrr: Permission denied
s" chmod 777 /tmp/trrr" system  ok
s" /tmp/trrr" w/o open-pipe .s <2> 94382312605664 0  ok
sh: 1: /tmp/trrr: Permission denied

Greetings,
Elko