nanogui@linuxhacker.org

: GR_CLIENT holds a client's event chain, and shared-memory speedup stuff
: for passing events and commands.  It also seems to be able to keep track
: of a list of clients, each with unique IDs (file descriptors?). 

GR_CLIENT is the structure that hold's each client event queue.
root_client is the head of the list.  


 I haven't
: found code in which such a list is constructed, although GsDropClient() in
: srvnet.c takes clients off of the list.

Grepping for GR_CLIENT shows that srvmain.c, function
GsClientAcceptFd builds a client event structure for a new
socket fd.

: 
: It looks like only one Nano-X client is permitted at the moment

No.  GsAcceptClientFd links each new client into the list.

Regards,

Greg