torsdag 31 januari 2013

Multiple ipv6 addresses on an interface

To prevent being tracked on the intertubes, ipv6 has security extensions that, (if they are enabled via sysctl net.ipv6.conf.all somewhere), from time to time creates random a address, and expire the old ones for outgoing traffic. To see the addresses do

ip -6 addr

and look for temporary.  The expired addresses (that still work) have the word "deprecated".  If you get sick of seeing them, delete an address from an interface with

ip -6 addr del dev eth0

or delete all deprecated addresses like this

ip -6 addr | awk '/deprecated/ {print "ip -6 addr del " $2 " dev eth0"}' | sudo bash -s

Virtual X11 display

x11vnc -create -forever -localhost

-create launches Xvfb  (on DISPLAY=:20 or something like that)
-forever enables reconnection
-localhost only listens to local connections, so you'll have to forward the port (5900+nr) for instance over ssh.

Then one may need a windowmanager too, for instance

DISPLAY=:10 fluxbox

You may put fluxbox in the .xinitrc file too.

torsdag 17 januari 2013

posting to xen-devel


example

git format-patch 73edc26b69803cdbce62513c7be8010c829e4274^..73edc26b69803cdbce62513c7be8010c829e4274

git send-email --in-reply-to '<1358428780 .13856.57.camel=".13856.57.camel" zakaz.uk.xensource.com="zakaz.uk.xensource.com">' --from lra@sics.se --to xen-devel@lists.xensource.com --smtp-server smtp.sics.se  0001-Set-register-values-and-comment-in-early-init_uart-t.patch



tisdag 15 januari 2013

inplace quicksort in python



https://gist.github.com/4537928


def quicksort(l):
work = [(0,len(l)-1)]
while work:
(left,right) = work.pop()
if right < left: 
continue
i_piv = left
piv = l[i_piv]
l0,r0 = left, right
while left < right:
while l[left] <= piv and left < right: left += 1
while l[right] > piv: right -= 1
if left < right: l[left], l[right] = l[right], l[left]
l[i_piv], l[right] = l[right], piv
work.append((l0,right-1))
work.append((right+1,r0))