[clamav-users] How to recompile with -fPIC?

[G.W. Haywood]

Hi there,

On Fri, 19 Jun 2020, Alberto Matxain wrote:

> I'm trying to install the latest version of clamav (0.102.3) on
> Ubuntu 20.04. I'm configuring clamav following the steps explained
> in
> http://www.clamav.net/documents/installation-on-debian-and-ubuntu-linux-distributions.

To be fair to you, that document isn't exactly beginner-friendly.

> It's the first time that I download the source code and I configure
> and compile a programme. I'm blocked because I don't know how to
> recompile with fPIC.
> ...
> ./configure --enable-check --disable-clamav --with-libjson-static=/usr/lib/x86_64-linux-gnu/libjson-c.a
> ...
> make -j2
> ...
> /usr/bin/ld: ... recompile with -fPIC

There are much easier ways to do what you want to do.  Version 0.102.3
of ClamaV is available in an Ubuntu package, so unless you're using an
architecture for which the package is not available (and I don't
believe that you are) then you could probably just install that:

https://packages.ubuntu.com/search?keywords=clamav&searchon=names&suite=focal&section=all

Even if you do want to compile it yourself, unless you want to have
more than one version of ClamAV running on your system (which I don't
recommend for a beginner), on an ordinary Ubuntu system I wouldn't
expect you to need any fancy options to 'configure'.  In that case I
would suggest, assuming that you've already installed dependencies:

1. Delete your existing clamav-0.102.3 source tree.
2. Extract the tarball once again into a new source tree(*).
3. Change your working directory to the top level of that tree.
4. Run the following comands verbatim - no options at all (**):
    ./configure
    make
    sudo make install

(*) Do this logged in as your usual user, in your home directory,
or somewhere that doesn't neeed administrator permissions to work.
(**) Run these commands as your usual user, not 'root'.  The last
command could be replaced by 'su root ; make install' which is how
I normally do it - but that's just because I have a sudo aversion.

Please let us know how you get on.  FWIW these are more or less the
steps to build anything supplied as a source tarball - at least if the
source is written largely in C (as is ClamAV).  Broadly speaking they
(1) set up the source tree to suit your system; (2) compile the source
thus set up to produce binaries and stuff in the source tree (but at
this stage it's _still_ all in your source tree); and (3) copy the
binaries, configuration files etc. (etc.) from the source tree into
the appropriate system areas - which is why that last step will need
administrator permissions.  Sometimes you can run the binaries while
they're still in the source tree, and if you do an optional but very
common 'make test' step before 'make install' that's what will happen.
I rarely bother doing that for ClamAV so I've left that part out for
simplicity, as the output might just give you more palpitations.

After you've done all this you should have ClamAV installed, and you
can get back to us to tell us what you want to do with it because it
will probably need some work to configure it to your liking.  ClamAV
is more along the lines of a toolkit than the point'n'shoot things you
see for Windows.  To be used effectively it needs some thought.

Please note that my list email address only accepts mail from the list.

-- 

73,
Ged.