1.SH 29P Protocol Drivers 3.PP 4The file server described so far 5waits for 9P protocol messages to 6appear in its input queue. 7It processes each message and 8sends the reply back to the originator. 9There are groups of processes that 10perform protocol I/O on some network or 11device and the resulting messages 12are sent to the file system queue. 13.PP 14There are two sets of processes 15.CW ethi 16and 17.CW etho 18that perform Ethernet input and output on two different networks. 19These processes send Ethernet messages 20to/from two more processes 21.CW ilo 22and 23.CW ilt 24that do the IL reliable datagram protocol 25on top of IP packets. 26.PP 27The last process in Emelie, 28.CW con , 29reads the console 30and calls internal subroutines to 31executes commands typed. 32Since there is only one process, 33only one command can be executing at a 34time. 35See 36.I fs (8) 37for a description of the 38commands available at the console. 39