First time in my life I have something like this:
root@peklan:~# aptitude install git-core
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.
FATAL -> Failed to fork.
can somebody explain how to get rid of this message?
that error message generally means aptitude or apt-get ran out of memory.
some suggestions:
if it's a VM, try increasing the RAM allocated to it. if it's a physical machine, try upgrading RAM.
if you've got lots of deb and deb-src entries in your sources.list file(s), then try commenting out most of them, running 'apt-get update', and 'apt-get install git-core'.
(definitely comment out all the deb-src entries unless you frequently rebuild debian source packages for some reason - most people don't.)
i'm not sure if it will help (probably won't), but you might also want to look at the Cache-Limit setting. see the man page for apt.conf for details, but in short add something like the following to /etc/apt/apt.conf or to a new text file in /etc/apt/apt.conf.d:
APT { Cache-Limit "56777216";} };
You can also add swap memory before you attempt to install the package.
You can add 512Mb swap by executing: