To install zgv, the following libraries should be installed, before trying
to make zgv:
libjpeg, libpcd, libpng, zlib

Having the libraries installed means the header files at some of the
standard include directories (usually at /usr/include or
/usr/local/include), and the library image (either shared or static) where
ld can find it.

After all the libraries are installed, 

make - to compile zgv
and
make install - installs the binary (suid root) as /usr/bin/zgv, and the
               man page at /usr/man/man1.
