lfs/chapter06/zlib.xml

<sect1 id="ch06-zlib">
<title>Installing Zlib-&zlib-version;</title>
<?dbhtml filename="zlib.html" dir="chapter06"?>

<screen>Estimated build time:           &zlib-time;
Estimated required disk space:  &zlib-compsize;</screen>

&aa-zlib-shortdesc;
&aa-zlib-dep;

<sect2><title>&nbsp;</title><para>&nbsp;</para></sect2>

<sect2>
<title>Installation of Zlib</title>

<para>Zlib has a potential buffer overflow in its
<emphasis>gzprintf()</emphasis> function, that, though difficult to take
advantage of, should be taken care of by applying this patch:</para>

<screen><userinput>patch -Np1 -i ../&zlib-patch;</userinput></screen>

<para>Now prepare Zlib for compilation:</para>

<screen><userinput>./configure --prefix=/usr --shared</userinput></screen>

<note><para>Zlib is known to build its shared library incorrectly if CFLAGS is
specified in the environment. If you are using your own CFLAGS variable, be
sure to add the <emphasis role="strong">-fPIC</emphasis> directive to your
CFLAGS for the duration of the above command, then remove it
afterwards.</para></note>

<para>Compile the package:</para>

<screen><userinput>make</userinput></screen>

<para>Install the shared libraries:</para>

<screen><userinput>make install</userinput></screen>

<para>Now also build the non-shared libraries:</para>
<screen><userinput>make clean
./configure --prefix=/usr
make</userinput></screen>

<para>This package has a test suite available which can perform a number of
checks to ensure it built correctly.  Should you choose to run it, the 
following command will do so:</para>

<screen><userinput>make test</userinput></screen>

<para>And install the package:</para>

<screen><userinput>make install</userinput></screen>

<para>The shared Zlib library should be installed in the
<filename>/lib</filename> directory. That way, in the event
that you must boot without the <filename>/usr</filename>
directory, vital system programs will still have access to
the library:</para>

<screen><userinput>mv /usr/lib/libz.so.* /lib</userinput></screen>

<para>The <filename>/usr/lib/libz.so</filename> symlink is
linked to a file which no longer exists, because we moved
it. Create a symbolic link to the new location of the
library:</para>

<screen><userinput>ln -sf ../../lib/libz.so.1 /usr/lib/libz.so</userinput></screen>

<para>Zlib does not install its manual page. Issue the
following command to install this documentation:</para>

<screen><userinput>cp zlib.3 /usr/share/man/man3</userinput></screen>

</sect2>

</sect1>