There is the free clamav software. On Ubuntu (at least 9.04 Jaunty and 9.10 Karmic) there are the following packages available:
anti-virus utility for Unix - command-line interface
anti-virus utility for Unix - base package
anti-virus utility for Unix - scanner daemon
anti-virus utility for Unix - virus database update utility
graphical front-end for ClamAV
KDE frontend for ClamAV
Antivirus scanning for Nautilus
There is one problem with the clamtk (the gnome GUI tool for scanning) - at least under Karmic used together with Thunderbird: Thunderbird tries to open all files with the clamtk and there if you change that it does not remember the change. And this although I don't want to scan everything automatically (even text files).
And there is a problem with with the nautilus-clamscan (at least under Karmic): It hangs in an infinite scan for the first file.
So whatever I tried, everything is annoying. Solved it the following way:
apt-get remove clamtkThen I created a new nautilus action (via System->Preferences->Nautilus Actions Configuration) with the following command (enabled for files and folders and multiple selections):
apt-get install nautilus-actions (if not already installed)
path: gnome-terminalAnd I have created the clamscan.sh with the following content (and set to be readable and executable for everyone):
parameters: -x /opt/clamscan.sh %M
Last but not least:
chmod 755 /opt/clamscan.sh
Now I can scan files with clamav on demand using the context menu in Nautilus.
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