Solution : Backtrack 5 apt-get upgrade error var/lib/dpkg/info/w3af.postins

If you ger below error ,simply download missing file to /tmp folder


system@bt:~# apt-get upgrade
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages have been kept back:
  smartphone-pentest-framework
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
1 not fully installed or removed.
After this operation, 0B of additional disk space will be used.
Do you want to continue [Y/n]? y
Setting up w3af (1.2-bt2) ...
tar: pybloomfiltermmap-0.2.0.tar.gz: Cannot open: No such file or directory
tar: Error is not recoverable: exiting now
tar: Child returned status 2
tar: Exiting with failure status due to previous errors
/var/lib/dpkg/info/w3af.postinst: line 4: cd: pybloomfiltermmap-0.2.0: No such file or directory
python: can't open file 'setup.py': [Errno 2] No such file or directory

system@bt:~# cd /tmp
system@bt:/tmp# 
wget http://pypi.python.org/packages/source/p/pybloomfiltermmap/pybloomfiltermmap-0.2.0.tar.gz

Now run upgrade
system@bt:~# apt-get upgrade