PHP Extension Writing Tutorial

Prerequisites

Before beginning this tutorial, you'll need a development environment with the following packages:

• Compiler: gcc and clang are both excellent choices.
• Build tools: autoconf, automake, libtool
• (Optional) parser generators: re2c and bison
• PHP 7.x with development headers:
  • Either distro packages such as: php7 and php7-devel
  • PHP compiled from source and installed with sudo make install. If compiling from source, then the --enable-debug switch is recommended, as well as the optional re2c and bison packages.
• libcurl and development headers: As part of this tutorial, we'll eventually be linking against libcurl. Install the library and it's associated development headers from your distro or install from source.

Obviously, you'll want this repo checked out in your build environment as well. Be sure to git pull to make sure you have the most recent version.

Format

This tutorial is split into steps, with one commit per step. At each commit, you should be able to compile the extension code as-provided using the following steps:

Generate ./configure script using phpize

$ phpize
Configuring for:
PHP Api Version:         20170718
Zend Module Api No:      20170718
Zend Extension Api No:   320170718

Generate Makefile using ./configure

$ ./configure
checking ...
checking ...
checking ...
[ lots of output ]
configure: creating ./config.status
config.status: creating config.h

Build your extension

$ make
/bin/bash .../libtool --mode=compile cc  -I. -DPHP_ATOM_INC -I/usr/local/include/php -I/usr/local/include/php/main -I/usr/local/include/php/TSRM -I/usr/local/include/php/Zend -I/usr/local/include/php/ext -DHAVE_CONFIG_H -g -O0 -c tutorial.c modules/tutorial.so

----------------------------------------------------------------------
Libraries have been installed in:
   .../modules

Build complete.
Don't forget to run 'make test'.

Check to be sure it loads

$ php -d extension=modules/tutorial.so --re tutorial
Extension [ <persistent> extension #40 tutorial version <no_version> ] {
}