Cleanup of doc files.

Fixed xterm.py (and cleanup) to clean up screen sessions.
Cleaned up sshd.py (though interface is still in flux.)
Added 1024-node network example (treenet1024.py).
Added example showing multiple tests on a single network (multitest.py).
Renamed examples to make them easier to type!

examples/xterms.py

@@ -1,11 +1,11 @@
 #!/usr/bin/python
 
 """
-Create a network and run an xterm (connected via screen(1) ) on each host.
-Requires xterm(1) and GNU screen(1).
+Create a network and run an xterm (connected via screen(1) ) on each
+host. Requires xterm(1) and GNU screen(1).
 """
 
-import os
+import os, re
 from subprocess import Popen
 from mininet import init, TreeNet, Cli, quietRun
 
@@ -13,18 +13,19 @@ def makeXterm( node, title ):
    "Run screen on a node, and hook up an xterm."
    node.cmdPrint( 'screen -dmS ' + node.name )
    title += ': ' + node.name
-   if not node.inNamespace:
-      title += ' (root namespace)'
+   if not node.inNamespace: title += ' (root)'
    cmd = [ 'xterm', '-title', title ]
    cmd += [ '-e', 'screen', '-D', '-RR', '-S', node.name ]
    return Popen( cmd )
 
 def cleanUpScreens():
    "Remove moldy old screen sessions."      
-   # XXX We need to implement this - otherwise those darned
-   # screen sessions will just accumulate
-   output = quietRun( 'screen -ls' )
-   pass
+   r = r'(\d+.[hsc]\d+)'
+   output = quietRun( 'screen -ls' ).split( '\n' )
+   for line in output:
+      m = re.search( r, line )
+      if m is not None:
+         quietRun( 'screen -S ' + m.group( 1 ) + ' -X kill' )
    
 def makeXterms( nodes, title ):
    terms = []
@@ -34,18 +35,18 @@ def makeXterms( nodes, title ):
    return terms
 
 def xterms( controllers, switches, hosts ):
+   cleanUpScreens()
    terms = []
    terms += makeXterms( controllers, 'controller' )
    terms += makeXterms( switches, 'switch' )
    terms += makeXterms( hosts, 'host' )
    # Wait for xterms to exit
-   for term in terms:
+   for term in terms: 
       os.waitpid( term.pid, 0 )
+   cleanUpScreens()
    
 if __name__ == '__main__':
    init()
    print "Running xterms on", os.environ[ 'DISPLAY' ]
-   cleanUpScreens()
    network = TreeNet( depth=2, fanout=2, kernel=True )
    network.run( xterms )
-   cleanUpScreens()