free linux AV noob Qs

Question

Spent life on windows. One month old on Ubuntu Unity. 
 Second install of Sophos free for Linux. (I got confused) 
 Below is end of install. does that mean anything to me? NOTE: You are running Sophos Anti-Virus on a kernel for which Sophos does not provide binary kernel modules. Therefore the kernel modules have been locally compiled. Please see KBA14377 for supported platforms and kernels. kris@kris-Z87N-WIFI:~/Downloads/SOPHOS AV/sophos-av$ Then ran savscan on Downloads with no problem. 
 I tested the first install yesterday on EICAR and worked fine.(FireFox) 
 Ran sudo /opt/sophos-av/bin/savupdate with no problem. I assume that updates the AV database...? How often do I need to run that? 
 Where do I find a list of the commands for this program? 
 EDIT: www.sophos.com/.../sophos-anti-virus-for-linux.aspx 
 Thanks!

DouglasLeeder · Accepted Answer

1) Each build of the Linux kernel requires a custom compiled set of kernel modules for the on-access anti-virus to intercept file operations. Sophos ships pre-compiled kernel modules for kernels on some supported platforms, and otherwise attempts to compile locally if on a different kernel. You are on a system running a kernel that Sophos doesn't ship pre-compiled binary modules for, so it has compiled locally. This is very common and nothing to worry about, but means you need to keep the compile environment installed when you update your kernel. 
 
2) savupdate is run automatically once an hour to update Sophos Anti-virus for Linux, so you don't need to run it yourself.

KrisMarkley · Answer

Thanks!