Clarified installation/enabling procedure. Also moved installation

instructions to the installation section from the requirements section.


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@345449 c90b9560-bf6c-de11-be94-00142212c4b1

reference/mysql_xdevapi/setup.xml

@@ -7,32 +7,66 @@
  <section xml:id="mysql-xdevapi.requirements">
   &reftitle.required;
   <para>
-   For compiling this extension Boost, OpenSSL, and Protobuf 
-   libraries are required as dependencies.
+   This extension requires a MySQL 8+ server with the X plugin 
+   enabled (default).
   </para>
   <para>
-   An example installation on Ubuntu 16.04:
+   Prerequisite libraries for compiling this extension are: 
+   Boost, OpenSSL, and Protobuf.
   </para>
-<programlisting>
-<![CDATA[
-$ apt install build-essential libprotobuf-dev libboost-dev openssl protobuf-compiler
 
-$ add-apt-repository ppa:ondrej/php
-$ apt install php7.1-cli php7.1-dev php7.1-mysql php7.1-pdo php7.1-xml
-
-$ pecl install mysql_xdevapi
-]]>
-</programlisting>
-  <para>
-   This extension requires a MySQL 8+ server with the X plugin enabled (default).
-  </para>
  </section>
 
  <section xml:id="mysql-xdevapi.installation">
   &reftitle.install;
+
   <para>
    &pecl.moved;
   </para>
+
+  <para>
+   An example installation procedure on Ubuntu 18.04 with PHP 7.2:
+  </para>
+<programlisting>
+<![CDATA[
+// Dependencies
+$ apt install build-essential libprotobuf-dev libboost-dev openssl protobuf-compiler
+
+// PHP with the desired extensions; php7.2-dev is required to compile
+$ apt install php7.2-cli php7.2-dev php7.2-mysql php7.2-pdo php7.2-xml
+
+// Compile the extension
+$ pecl install mysql_xdevapi
+]]>
+</programlisting>
+
+  <para>
+    The <literal>pecl install</literal> command does not enable PHP extensions (by default)
+    and enabling PHP extensions can be done in several ways. 
+    Another PHP 7.2 on Ubuntu 18.04 example:
+  </para>
+
+<programlisting>
+<![CDATA[
+// Create its own ini file
+$ echo "extension=mysql_xdevapi.so" > /etc/php/7.2/mods-available/mysql_xdevapi.ini
+
+// Use the 'phpenmod' command (note: it's Debian/Ubuntu specific)
+$ phpenmod -v 7.2 -s ALL mysql_xdevapi
+
+// A 'phpenmod' alternative is to manually symlink it
+// $ ln -s /etc/php/7.2/mods-available/mysql_xdevapi.ini /etc/php/7.2/cli/conf.d/20-mysql_xdevapi.ini
+
+// Let's see which MySQL extensions are enabled now
+$ php -m |grep mysql
+
+mysql_xdevapi
+mysqli
+mysqlnd
+pdo_mysql
+]]>
+</programlisting>
+
   <para>
    &pecl.info;
    <link xlink:href="&url.pecl.package;apc">&url.pecl.package;mysql_xdevapi</link>.