alue of <tt>deflateInit()</tt> against the <em>zlib</em> constant
<tt>Z_OK</tt> to make sure that it was able to
allocate memory for the internal state, and that the provided arguments were valid.
<tt>deflateInit()</tt> will also check that the version of <em>zlib</em> that the <tt>zlib.h</tt>
file came from matches the version of <em>zlib</em> actually linked with the program.  This
is especially important for environments in which <em>zlib</em> is a shared library.
<p>
Note that an application can initial