package kdoctools 4:4.7.2-0ubuntu2 failed to install/upgrade: unable to create `/usr/share/man/man8/meinproc4.8.gz.dpkg-new' (while processing `./usr/share/man/man8/meinproc4.8.gz'): Invalid argument

basically - i haven't been able to download any software on ubuntu - nothing is working. I am using it from my 4 gb usb drive which is almost full , so maybe that is the constraint. But i don't know for sure. What's the cause of this problem? Please do help me find and fix it, as best as you can!
Thanks.

ProblemType: Package
DistroRelease: Ubuntu 11.10
Package: kdoctools 4:4.7.2-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
CasperVersion: 1.287
Date: Sun Nov 20 12:09:36 2011
Df:

DuplicateSignature:
 Unpacking kdoctools (from .../kdoctools_4%3a4.7.2-0ubuntu2_amd64.deb) ...
 dpkg: error processing /var/cache/apt/archives/kdoctools_4%3a4.7.2-0ubuntu2_amd64.deb (--unpack):
  unable to create `/usr/share/man/man8/meinproc4.8.gz.dpkg-new' (while processing `./usr/share/man/man8/meinproc4.8.gz'): Invalid argument
ErrorMessage: unable to create `/usr/share/man/man8/meinproc4.8.gz.dpkg-new' (while processing `./usr/share/man/man8/meinproc4.8.gz'): Invalid argument
LiveMediaBuild: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: kde4libs
Title: package kdoctools 4:4.7.2-0ubuntu2 failed to install/upgrade: unable to create `/usr/share/man/man8/meinproc4.8.gz.dpkg-new' (while processing `./usr/share/man/man8/meinproc4.8.gz'): Invalid argument
UpgradeStatus: Upgraded to oneiric on 2011-11-20 (0 days ago)