Installing ClamAV:
You can install one of the two packages depending upon how you are going
to use the antivirus. If you are going to use it manually, means starting the
antivirus when required. In this case you should get the clamav package.
sudo apt-get install clamav
For automated use install the package clamav-daemon
sudo apt-get install clamav-daemon
After installing you may be asked to configure the antivirus like updates, I
recommend automatically since its updates are very small.
Scanning Using ClamAV:
Use the command clamscan
Let’s check out some examples
To check each file, displaying name of each file: clamscan –r /
To check all files,display only infected file and ring a bell if infected files are
found: clamscan -r –bell -i /
After scan is completed it generates a scan summary.
Updating virus definitions:
Use the command freshclam
Finally one more point, clamscan can inspect only those file for which the
user is authorized to read. For checking all files use sudo prefix.