add-apt-repository returns unexpected length error
Solution 1:
It appears this is a known issue/bug, you could try this workaround:
To install PPA's, add them to /etc/apt/sources.list in the form:
Before:
ppa:<user>/<repo>
Add to sources.list:
deb http://ppa.launchpad.net/<user>/<repo>/ubuntu oneiric main
Then sudo apt-get update and download whatever packages you want.
Solution 2:
In my case,and that worked, that's what I did in Ubuntu 12.04:
sudo apt-get clean
sudo apt-get update
And then I tried to add my ppa as usual :
sudo add-apt-repository ppa:.../...
Hopes it works for everyone !