<HTML ><HEAD ><TITLE >Using Extensions</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="PHP Manual" HREF="index.html"><LINK REL="UP" TITLE="Extending PHP 4.0" HREF="zend.html"><LINK REL="PREVIOUS" TITLE="Creating Extensions" HREF="zend.creating.html"><LINK REL="NEXT" TITLE="Troubleshooting" HREF="zend.troubleshooting.html"><META HTTP-EQUIV="Content-type" CONTENT="text/html; charset=ISO-8859-1"></HEAD ><BODY CLASS="chapter" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >PHP Manual</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="zend.creating.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="zend.troubleshooting.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="chapter" ><H1 ><A NAME="zend.using" >Chapter 29. Using Extensions</A ></H1 ><P > Depending on the build process you selected, you should either end up with a new PHP binary to be linked into your Web server (or run as CGI), or with an .so (shared object) file. If you compiled the example file <TT CLASS="filename" >first_module.c</TT > as a shared object, your result file should be <TT CLASS="filename" >first_module.so</TT >. To use it, you first have to copy it to a place from which it's accessible to PHP. For a simple test procedure, you can copy it to your <TT CLASS="filename" >htdocs</TT > directory and try it with the source in <A HREF="zend.using.html#example.testfile" >Example 29-1</A >. If you compiled it into the PHP binary, omit the call to <A HREF="function.dl.html" ><B CLASS="function" >dl()</B ></A >, as the module's functionality is instantly available to your scripts. <DIV CLASS="warning" ><P ></P ><TABLE CLASS="warning" BORDER="1" WIDTH="100%" ><TR ><TD ALIGN="CENTER" ><B >Warning</B ></TD ></TR ><TR ><TD ALIGN="LEFT" ><P > For security reasons, you <SPAN CLASS="emphasis" ><I CLASS="emphasis" >should not</I ></SPAN > put your dynamic modules into publicly accessible directories. Even though it <SPAN CLASS="emphasis" ><I CLASS="emphasis" >can</I ></SPAN > be done and it simplifies testing, you should put them into a separate directory in production environments. </P ></TD ></TR ></TABLE ></DIV > </P ><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="example.testfile" ></A ><P ><B >Example 29-1. A test file for first_module.so.</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><PRE CLASS="php" ><?php // remove next comment if necessary // dl("first_module.so"); $param = 2; $return = first_module($param); print("We sent '$param' and got '$return'"); ?></PRE ></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE ><P > Calling this PHP file in your Web browser should give you the output shown in <A HREF="zend.using.html#fig.out-first" >Figure 29-1</A >. <DIV CLASS="figure" ><A NAME="fig.out-first" ></A ><P ><B >Figure 29-1. Output of first_module.php.</B ></P ><P ><IMG SRC="figures/Extending_Zend_2_firstmod_output.png"></P ></DIV > </P ><P > If required, the dynamic loadable module is loaded by calling the <A HREF="function.dl.html" ><B CLASS="function" >dl()</B ></A > function. This function looks for the specified shared object, loads it, and makes its functions available to PHP. The module exports the function <B CLASS="function" >first_module()</B >, which accepts a single parameter, converts it to an integer, and returns the result of the conversion. </P ><P > If you've gotten this far, congratulations! You just built your first extension to PHP. </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="zend.creating.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="zend.troubleshooting.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Creating Extensions</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="zend.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Troubleshooting</TD ></TR ></TABLE ></DIV ></BODY ></HTML >