1.) Is there any way to get the machine to check its local host table
    first without renaming resolv.conf?

[AIX 3.2 only]
PTF U412845 implements an environment variable to set the resolver
time out in AIX 3.2.  This allows you to set RES_TIMEOUT to the number
of seconds before it times out, a failing a DNS query the machine will
consult /etc/hosts.  

2.) How do you tell X applications where you are if the console display 
    is unix:0?

From: David L. Crow <crow@waterloo.austin.ibm.com>

  I would suggest that if you have R5, use ":<display>.<screen>".  I do
  not believe that R4 clients will understand :0, so I would suggest
  unix:0 for them.

  Without specifying unix or the hostname, you will get the fastest
  transport mechanism.  While currently there are only two transport
  methods in the AIXwindows X server (Unix sockets and TCP sockets),
  many vendors are looking at using shared memory as a transport method. 
  If you use :0 (or :0.0 or :1, etc.), then you should get the best
  performance regardless of the available transport methods.

From: Marc Pawliger <marc@sti.com>

  Using "unix:0" or "hostname:0" when the X11 Shared Memory Transport
(SMT) is installed as part of the 1.2.3 X11rte.obj (X11R5) will incur
a penalty vs. using ":0" See /usr/lpp/X11/README.SMT

3.) Is there a significant performance penalty incurred by using
    `hostname`:0 as DISPLAY?

  Yes! Using unix:0, you are using Unix sockets.  These are much faster
  than their TCP socket counterparts.

Some parts © 2009 Advameg, Inc.