Using NamedPipeServerStream to read and NamedPipeClientStream to write data, everything works fine when both processes are run by the same user, but if I run the client process by a different user I get Permission denied /tmp/CoreFxPipe_my_pipe. The pipe "file" indeed doesn't have write permissions for other users.
PipeOptions has a member CurrentUserOnly, but I didn't set it (I even tried setting None explicitly). How can I allow other users to write to the pipe?