One of the simplest C extensions for php

To write a php extension, we can first download the source code of a php version, and then enter the ext directory of php. For example, my local version is php5.4.

<code>andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext<span>$ </span>./ext_skel --extname=andy
<span>Creating</span> directory andy
<span>Creating</span> basic <span>files:</span> config.m4 config.w32 .svnignore andy.c php_andy.h <span>CREDITS</span><span>EXPERIMENTAL</span> tests/<span>001</span>.phpt andy.php [done].

<span>To</span> use your new extension, you will have to execute the following <span>steps:</span><span>1</span>.  <span>$ </span>cd ..
<span>2</span>.  <span>$ </span>vi ext/andy/config.m4
<span>3</span>.  <span>$ </span>./buildconf
<span>4</span>.  <span>$ </span>./configure --[with|enable]-andy
<span>5</span>.  <span>$ </span>make
<span>6</span>.  <span>$ </span>./sapi/cli/php -f ext/andy/andy.php
<span>7</span>.  <span>$ </span>vi ext/andy/andy.c
<span>8</span>.  <span>$ </span>make

<span>Repeat</span> steps <span>3</span>-<span>6</span><span>until</span> you are satisfied with ext/andy/config.m4 <span>and</span>
step <span>6</span> confirms that your <span><span>module</span><span>is</span><span>compiled</span><span>into</span><span>PHP</span>. <span>Then</span>, <span>start</span><span>writing</span></span>
code <span>and</span> repeat the last two steps as often as necessary.

andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext<span>$ </span>cd andy/
andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext/andy<span>$ </span>ll
total <span>64</span>
drwxr-xr-x  <span>11</span> andy  staff   <span>374</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> ./
drwxr-xr-x@ <span>81</span> andy  staff  <span>2754</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> ../
-rw-r--r--   <span>1</span> andy  staff    <span>16</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> .svnignore
-rw-r--r--   <span>1</span> andy  staff     <span>5</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span><span>CREDITS</span>
-rw-r--r--   <span>1</span> andy  staff     <span>0</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span><span>EXPERIMENTAL</span>
-rw-r--r--   <span>1</span> andy  staff  <span>5044</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> andy.c
-rw-r--r--   <span>1</span> andy  staff   <span>496</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> andy.php
-rw-r--r--   <span>1</span> andy  staff  <span>1970</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> config.m4
-rw-r--r--   <span>1</span> andy  staff   <span>282</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> config.w32
-rw-r--r--   <span>1</span> andy  staff  <span>2812</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> php_andy.h
drwxr-xr-x   <span>3</span> andy  staff   <span>102</span><span>2</span><span>6</span><span>11</span><span>:</span><span>42</span> tests/
andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext/andy$</code>

Then edit the config.m4 and change it to the following:

<code>PHP_ARG_WITH(andy, <span>for</span> andy support,
[  <span>--with-andy             Include andy support])</span>dnl Otherwise <span>use</span> enable:

PHP_ARG_ENABLE(andy, whether <span>to</span> enable andy support,
[  <span>--enable-andy           Enable andy support])</span><span>if</span> test <span>"$PHP_ANDY"</span> != <span>"no"</span>; <span>then</span>
  PHP_NEW_EXTENSION(andy, andy.c, $ext_shared)
fi</code>

dnl represents the comment

Then we modify the header file: php_andy.h

<code><span>PHP_FUNCTION(confirm_andy_compiled)</span>;    <span>/* For testing, remove later. */</span><span>PHP_FUNCTION(andy_whoami)</span>;</code>

PHP_FUNCTION(andy_whoami); This section allows us to add, nightly is the extension function declaration part that we will add.

Then we modify andy.c, which is the function body. We register the pointer of our function whoami to PHP_FE:

<code><span>/* </span><span>{{{ <span>andy</span>_<span>functions</span>[]
 *
 * <span>Every</span><span>user</span><span>visible</span><span>function</span><span>must</span><span>have</span><span>an</span><span>entry</span><span><span>in</span></span><span>andy</span>_<span>functions</span>[]<span>.</span>
 */
<span>const</span><span>zend</span>_<span>function</span>_<span>entry</span><span>andy</span>_<span>functions</span>[] = {
    <span>PHP</span>_<span>FE</span>(<span>confirm</span>_<span>andy</span>_<span>compiled</span>,   <span>NULL</span>)       /* <span>For</span><span>testing</span>, <span>remove</span><span>later.</span> */
    <span>PHP</span>_<span>FE</span>(<span>andy</span>_<span>whoami</span>, <span>NULL</span>)       /* <span>my</span><span>def</span><span>function</span> : <span>whoami.</span> */
    <span>PHP</span>_<span>FE</span>_<span>END</span>  /* <span>Must</span><span>be</span><span>the</span><span>last</span><span>line</span><span><span>in</span></span><span>andy</span>_<span>functions</span>[] */
};
/* }}</span><span>} */</span></code>

Then we edit the function part, andy.c, and add this code in the last part:

<code>PHP_FUNCTION(andy_whoami){
    <span>char</span> *arg = <span>null</span>;
    <span>int</span> arg_len, len;
    <span>char</span> *strg;
    <span>if</span>(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, <span>"s"</span>, &arg, &arg_len) == <span>false</span>){
        <span>return</span>;
    }
    php_printf(<span>"I'm andy,It's nice to meet you. wish we could be happy together :-)."</span>);
    RETURN_TRUE;
}</code>

After that, we save and exit. Then in the directory, we should perform phpize,./configure, make, and make install all at once:

<code>andy@AndyMacBookPro:~/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy$ phpize
Configuring for:
PHP Api Version:         <span>20100412</span>
Zend Module Api No:      <span>20100525</span>
Zend Extension Api No:   <span>220100525</span>
andy@AndyMacBookPro:~/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy$ ll
total <span>2448</span>
drwxr<span>-xr</span><span>-x</span><span>27</span> andy  staff     <span>918</span><span>2</span><span>6</span><span>14</span>:<span>29</span><span>.</span><span>/</span>
drwxr<span>-xr</span><span>-x</span>@ <span>81</span> andy  staff    <span>2754</span><span>2</span><span>6</span><span>11</span>:<span>42</span><span>..</span><span>/</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff      <span>16</span><span>2</span><span>6</span><span>11</span>:<span>42</span><span>.</span>svnignore
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff       <span>5</span><span>2</span><span>6</span><span>11</span>:<span>42</span> CREDITS
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff       <span>0</span><span>2</span><span>6</span><span>11</span>:<span>42</span> EXPERIMENTAL
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>5607</span><span>2</span><span>6</span><span>14</span>:<span>29</span> Makefile<span>.</span><span>global</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff   <span>79851</span><span>2</span><span>6</span><span>14</span>:<span>29</span> acinclude<span>.</span>m4
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff  <span>310175</span><span>2</span><span>6</span><span>14</span>:<span>29</span> aclocal<span>.</span>m4
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>5415</span><span>2</span><span>6</span><span>14</span>:<span>27</span> andy<span>.</span>c
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff     <span>496</span><span>2</span><span>6</span><span>11</span>:<span>42</span> andy<span>.</span>php
drwxr<span>-xr</span><span>-x</span><span>5</span> andy  staff     <span>170</span><span>2</span><span>6</span><span>14</span>:<span>29</span> autom4te<span>.</span><span>cache</span><span>/</span>
drwxr<span>-xr</span><span>-x</span><span>6</span> andy  staff     <span>204</span><span>2</span><span>6</span><span>14</span>:<span>29</span> build<span>/</span><span>-rwxr</span><span>-xr</span><span>-x</span><span>1</span> andy  staff   <span>44893</span><span>2</span><span>6</span><span>14</span>:<span>29</span> config<span>.</span>guess<span>*</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>1598</span><span>2</span><span>6</span><span>14</span>:<span>29</span> config<span>.</span>h<span>.</span><span>in</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>1868</span><span>2</span><span>6</span><span>11</span>:<span>57</span> config<span>.</span>m4
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>1970</span><span>2</span><span>6</span><span>11</span>:<span>42</span> config<span>.</span>m4<span>.</span>bak
<span>-rwxr</span><span>-xr</span><span>-x</span><span>1</span> andy  staff   <span>33399</span><span>2</span><span>6</span><span>14</span>:<span>29</span> config<span>.</span>sub<span>*</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff     <span>282</span><span>2</span><span>6</span><span>11</span>:<span>42</span> config<span>.</span>w32
<span>-rwxr</span><span>-xr</span><span>-x</span><span>1</span> andy  staff  <span>437790</span><span>2</span><span>6</span><span>14</span>:<span>29</span> configure<span>*</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>4690</span><span>2</span><span>6</span><span>14</span>:<span>29</span> configure<span>.</span><span>in</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff       <span>0</span><span>2</span><span>6</span><span>14</span>:<span>29</span> install<span>-sh</span><span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff  <span>199728</span><span>2</span><span>6</span><span>14</span>:<span>29</span> ltmain<span>.</span>sh
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff       <span>0</span><span>2</span><span>6</span><span>14</span>:<span>29</span> missing
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff       <span>0</span><span>2</span><span>6</span><span>14</span>:<span>29</span> mkinstalldirs
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff    <span>2839</span><span>2</span><span>6</span><span>12</span>:<span>04</span> php_andy<span>.</span>h
<span>-rw</span><span>-r</span><span>--</span>r<span>--</span><span>1</span> andy  staff   <span>79503</span><span>2</span><span>6</span><span>14</span>:<span>29</span> run<span>-tests</span><span>.</span>php
drwxr<span>-xr</span><span>-x</span><span>3</span> andy  staff     <span>102</span><span>2</span><span>6</span><span>11</span>:<span>42</span> tests<span>/</span>
andy@AndyMacBookPro:~/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy$ <span>.</span>/configure
checking for grep that handles long lines <span>and</span><span>-e</span><span>...</span> /usr/bin/grep
checking for egrep<span>...</span> /usr/bin/grep <span>-E</span>
checking for a sed that does <span>not</span> truncate output<span>...</span> /usr/bin/sed
checking for cc<span>...</span> cc
checking whether the C compiler works<span>...</span> yes
checking for C compiler default output file name<span>...</span> a<span>.</span>out
checking for suffix of executables<span>...</span>
checking whether we are cross compiling<span>...</span> no
checking for suffix of object files<span>...</span> o
checking whether we are using the GNU C compiler<span>...</span> yes
checking whether cc accepts <span>-g</span><span>...</span> yes
checking for cc option <span>to</span> accept ISO C89<span>...</span><span>none</span> needed
checking how <span>to</span> run the C preprocessor<span>...</span> cc <span>-E</span>
checking for icc<span>...</span> no
checking for suncc<span>...</span> no
checking whether cc understands <span>-c</span><span>and</span><span>-o</span> together<span>...</span> yes
checking for system library directory<span>...</span> lib
checking <span>if</span> compiler supports <span>-R</span><span>...</span> no
checking <span>if</span> compiler supports <span>-Wl</span>,<span>-rpath</span>,<span>...</span> yes
checking build system <span>type</span><span>...</span> i386<span>-apple</span><span>-darwin13</span><span>.4</span><span>.0</span>
checking host system <span>type</span><span>...</span> i386<span>-apple</span><span>-darwin13</span><span>.4</span><span>.0</span>
checking target system <span>type</span><span>...</span> i386<span>-apple</span><span>-darwin13</span><span>.4</span><span>.0</span>
checking for PHP prefix<span>...</span> /usr
checking for PHP includes<span>...</span><span>-I</span>/usr/include/php <span>-I</span>/usr/include/php/main <span>-I</span>/usr/include/php/TSRM <span>-I</span>/usr/include/php/Zend <span>-I</span>/usr/include/php/ext <span>-I</span>/usr/include/php/ext/<span>date</span>/lib
checking for PHP extension directory<span>...</span> /usr/lib/php/extensions/no<span>-debug</span><span>-non</span><span>-zts</span><span>-</span><span>20100525</span>
checking for PHP installed headers prefix<span>...</span> /usr/include/php
checking <span>if</span> debug is enabled<span>...</span> no
checking <span>if</span> zts is enabled<span>...</span> no
checking for re2c<span>...</span> no
configure: WARNING: You will need re2c <span>0.13</span><span>.4</span><span>or</span> later <span>if</span> you want <span>to</span> regenerate PHP parsers<span>.</span>
checking for gawk<span>...</span> no
checking for nawk<span>...</span> no
checking for awk<span>...</span> awk
checking <span>if</span> awk is broken<span>...</span> no
checking for andy support<span>...</span> yes, shared
checking whether <span>to</span> enable andy support<span>...</span> yes, shared
checking for ld used <span>by</span> cc<span>...</span> /Applications/Xcode<span>.</span>app/Contents/Developer/Toolchains/XcodeDefault<span>.</span>xctoolchain/usr/bin/ld
checking <span>if</span> the linker (/Applications/Xcode<span>.</span>app/Contents/Developer/Toolchains/XcodeDefault<span>.</span>xctoolchain/usr/bin/ld) is GNU ld<span>...</span> no
checking for /Applications/Xcode<span>.</span>app/Contents/Developer/Toolchains/XcodeDefault<span>.</span>xctoolchain/usr/bin/ld option <span>to</span> reload object files<span>...</span><span>-r</span>
checking for BSD<span>-compatible</span> nm<span>...</span> /usr/bin/nm
checking whether ln <span>-s</span> works<span>...</span> yes
checking how <span>to</span> recognize dependent libraries<span>...</span> pass_all
checking for ANSI C <span>header</span> files<span>...</span> yes
checking for sys/types<span>.</span>h<span>...</span> yes
checking for sys/stat<span>.</span>h<span>...</span> yes
checking for stdlib<span>.</span>h<span>...</span> yes
checking for <span>string</span><span>.</span>h<span>...</span> yes
checking for memory<span>.</span>h<span>...</span> yes
checking for strings<span>.</span>h<span>...</span> yes
checking for inttypes<span>.</span>h<span>...</span> yes
checking for stdint<span>.</span>h<span>...</span> yes
checking for unistd<span>.</span>h<span>...</span> yes
checking dlfcn<span>.</span>h usability<span>...</span> yes
checking dlfcn<span>.</span>h presence<span>...</span> yes
checking for dlfcn<span>.</span>h<span>...</span> yes
checking the maximum length of command line arguments<span>...</span><span>196608</span>
checking command <span>to</span> parse /usr/bin/nm output from cc object<span>...</span> ok
checking for objdir<span>...</span><span>.</span>libs
checking for ar<span>...</span> ar
checking for ranlib<span>...</span> ranlib
checking for strip<span>...</span> strip
checking for dsymutil<span>...</span> dsymutil
checking for nmedit<span>...</span> nmedit
checking for <span>-single_module</span> linker flag<span>...</span> yes
checking for <span>-exported_symbols_list</span> linker flag<span>...</span> yes
checking <span>if</span> cc supports <span>-fno</span><span>-rtti</span><span>-fno</span><span>-exceptions</span><span>...</span> yes
checking for cc option <span>to</span> produce PIC<span>...</span><span>-fno</span><span>-common</span>
checking <span>if</span> cc PIC flag <span>-fno</span><span>-common</span> works<span>...</span> yes
checking <span>if</span> cc static flag <span>-static</span> works<span>...</span> no
checking <span>if</span> cc supports <span>-c</span><span>-o</span> file<span>.</span>o<span>...</span> yes
checking whether the cc linker (/Applications/Xcode<span>.</span>app/Contents/Developer/Toolchains/XcodeDefault<span>.</span>xctoolchain/usr/bin/ld) supports shared libraries<span>...</span> yes
checking dynamic linker characteristics<span>...</span> darwin13<span>.4</span><span>.0</span> dyld
checking how <span>to</span> hardcode library paths <span>into</span> programs<span>...</span> immediate
checking whether stripping libraries is possible<span>...</span> yes
checking <span>if</span> libtool supports shared libraries<span>...</span> yes
checking whether <span>to</span> build shared libraries<span>...</span> yes
checking whether <span>to</span> build static libraries<span>...</span> no

creating libtool
appending configuration <span>tag</span><span>"CXX"</span><span>to</span> libtool
configure: creating <span>.</span>/config<span>.</span>status
config<span>.</span>status: creating config<span>.</span>h
andy@AndyMacBookPro:~/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy$ make
/bin/sh /Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/libtool <span>--</span>mode<span>=</span>compile cc  <span>-I</span><span>.</span><span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy <span>-DPHP_ATOM_INC</span><span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/include <span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/main <span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy <span>-I</span>/usr/include/php <span>-I</span>/usr/include/php/main <span>-I</span>/usr/include/php/TSRM <span>-I</span>/usr/include/php/Zend <span>-I</span>/usr/include/php/ext <span>-I</span>/usr/include/php/ext/<span>date</span>/lib  <span>-DHAVE_CONFIG_H</span><span>-g</span><span>-O2</span><span>-c</span> /Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/andy<span>.</span>c <span>-o</span> andy<span>.</span>lo
mkdir <span>.</span>libs
 cc <span>-I</span><span>.</span><span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy <span>-DPHP_ATOM_INC</span><span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/include <span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/main <span>-I</span>/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy <span>-I</span>/usr/include/php <span>-I</span>/usr/include/php/main <span>-I</span>/usr/include/php/TSRM <span>-I</span>/usr/include/php/Zend <span>-I</span>/usr/include/php/ext <span>-I</span>/usr/include/php/ext/<span>date</span>/lib <span>-DHAVE_CONFIG_H</span><span>-g</span><span>-O2</span><span>-c</span> /Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/andy<span>.</span>c  <span>-fno</span><span>-common</span><span>-DPIC</span><span>-o</span><span>.</span>libs/andy<span>.</span>o
/Users/andy/Downloads/php<span>-</span><span>5.4</span><span>.30</span>/ext/andy/andy<span>.</span>c:<span>187</span>:<span>14</span>: error: use of
      undeclared identifier <span>'null'</span>
        char <span>*</span>arg <span>=</span><span>null</span>;
                    ^
<span>1</span> error generated<span>.</span>
make: <span>***</span><span>[</span>andy<span>.</span>lo<span>]</span><span> Error 1
andy@AndyMacBookPro:~/Downloads/php-5.4.30/ext/andy$</span></code>

I found that there was a problem with my source code. It should be capitalized NULL, so I went back to modify it, and then restarted after modification. Compiled successfully:

<code>andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext/andy<span>$ </span>make
/bin/sh /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/libtool --mode=compile cc  -<span>I</span>. -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>DPHP_ATOM_INC</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/<span>include</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/main -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>I</span>/usr/<span>include</span>/php -<span>I</span>/usr/<span>include</span>/php/main -<span>I</span>/usr/<span>include</span>/php/<span>TSRM</span> -<span>I</span>/usr/<span>include</span>/php/<span>Zend</span> -<span>I</span>/usr/<span>include</span>/php/ext -<span>I</span>/usr/<span>include</span>/php/ext/date/lib  -<span>DHAVE_CONFIG_H</span>  -g -<span>O2</span>   -c /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/andy.c -o andy.lo
mkdir .libs
 cc -<span>I</span>. -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>DPHP_ATOM_INC</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/<span>include</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/main -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>I</span>/usr/<span>include</span>/php -<span>I</span>/usr/<span>include</span>/php/main -<span>I</span>/usr/<span>include</span>/php/<span>TSRM</span> -<span>I</span>/usr/<span>include</span>/php/<span>Zend</span> -<span>I</span>/usr/<span>include</span>/php/ext -<span>I</span>/usr/<span>include</span>/php/ext/date/lib -<span>DHAVE_CONFIG_H</span> -g -<span>O2</span> -c /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/andy.c  -fno-common -<span>DPIC</span> -o .libs/andy.o
/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/andy.<span>c:</span><span>187</span><span>:</span><span>14</span><span>:</span><span>error:</span> use of
      undeclared identifier <span>'null'</span>
        char *arg = null;
                    ^
<span>1</span> error generated.
<span>make:</span> *** [andy.lo] <span>Error</span><span>1</span>
andy<span>@AndyMacBookPro</span><span>:~/Downloads/php-</span><span>5.4</span>.<span>30</span>/ext/andy<span>$ </span>make
/bin/sh /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/libtool --mode=compile cc  -<span>I</span>. -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>DPHP_ATOM_INC</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/<span>include</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/main -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>I</span>/usr/<span>include</span>/php -<span>I</span>/usr/<span>include</span>/php/main -<span>I</span>/usr/<span>include</span>/php/<span>TSRM</span> -<span>I</span>/usr/<span>include</span>/php/<span>Zend</span> -<span>I</span>/usr/<span>include</span>/php/ext -<span>I</span>/usr/<span>include</span>/php/ext/date/lib  -<span>DHAVE_CONFIG_H</span>  -g -<span>O2</span>   -c /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/andy.c -o andy.lo
 cc -<span>I</span>. -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>DPHP_ATOM_INC</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/<span>include</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/main -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>I</span>/usr/<span>include</span>/php -<span>I</span>/usr/<span>include</span>/php/main -<span>I</span>/usr/<span>include</span>/php/<span>TSRM</span> -<span>I</span>/usr/<span>include</span>/php/<span>Zend</span> -<span>I</span>/usr/<span>include</span>/php/ext -<span>I</span>/usr/<span>include</span>/php/ext/date/lib -<span>DHAVE_CONFIG_H</span> -g -<span>O2</span> -c /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/andy.c  -fno-common -<span>DPIC</span> -o .libs/andy.o
/bin/sh /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/libtool --mode=link cc -<span>DPHP_ATOM_INC</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/<span>include</span> -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/main -<span>I</span>/<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy -<span>I</span>/usr/<span>include</span>/php -<span>I</span>/usr/<span>include</span>/php/main -<span>I</span>/usr/<span>include</span>/php/<span>TSRM</span> -<span>I</span>/usr/<span>include</span>/php/<span>Zend</span> -<span>I</span>/usr/<span>include</span>/php/ext -<span>I</span>/usr/<span>include</span>/php/ext/date/lib  -<span>DHAVE_CONFIG_H</span>  -g -<span>O2</span>   -o andy.la -export-dynamic -avoid-version -prefer-pic -<span><span>module</span> -<span>rpath</span> /<span>Users</span>/<span>andy</span>/<span>Downloads</span>/<span>php</span>-5.4.30/<span>ext</span>/<span>andy</span>/<span>modules</span><span>andy</span>.<span>lo</span></span>
cc <span>${</span>wl}-flat_namespace <span>${</span>wl}-undefined <span>${</span>wl}suppress -o .libs/andy.so -bundle  .libs/andy.o
dsymutil .libs/andy.so || <span>:</span>
creating andy.la
(cd .libs && rm -f andy.la && ln -s ../andy.la andy.la)
/bin/sh /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/libtool --mode=install cp ./andy.la /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/modules
cp ./.libs/andy.so /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/modules/andy.so
cp ./.libs/andy.lai /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/modules/andy.la
----------------------------------------------------------------------
<span>Libraries</span> have been installed <span>in:</span>
   /<span>Users</span>/andy/<span>Downloads</span>/php-<span>5.4</span>.<span>30</span>/ext/andy/modules

<span>If</span> you ever happen to want to link against installed libraries
<span>in</span> a given directory, <span>LIBDIR</span>, you must either use libtool, <span>and</span>
specify the full pathname of the library, <span>or</span> use the `-<span>LLIBDIR</span><span>'
flag during linking and do at least one of the following:
   - add LIBDIR to the `DYLD_LIBRARY_PATH'</span> environment variable
     during execution

<span>See</span> any operating system documentation about shared libraries <span>for</span>
more information, such as the ld(<span>1</span>) <span>and</span> ld.so(<span>8</span>) manual pages.
----------------------------------------------------------------------

<span>Build</span> complete.
<span>Don</span><span>'t forget to run '</span>make test<span>'.

andy@AndyMacBookPro:~/Downloads/php-5.4.30/ext/andy$ make install
Installing shared extensions:     /usr/lib/php/extensions/no-debug-non-zts-20100525/
cp: /usr/lib/php/extensions/no-debug-non-zts-20100525/#INST@3154#: Permission denied
make: *** [install-modules] Error 1
andy@AndyMacBookPro:~/Downloads/php-5.4.30/ext/andy$ sudo make install
Password:
/bin/sh /Users/andy/Downloads/php-5.4.30/ext/andy/libtool --mode=install cp ./andy.la /Users/andy/Downloads/php-5.4.30/ext/andy/modules
cp ./.libs/andy.so /Users/andy/Downloads/php-5.4.30/ext/andy/modules/andy.so
cp ./.libs/andy.lai /Users/andy/Downloads/php-5.4.30/ext/andy/modules/andy.la
----------------------------------------------------------------------
Libraries have been installed in:
   /Users/andy/Downloads/php-5.4.30/ext/andy/modules

If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR'</span>
flag during linking <span>and</span><span>do</span> at least one of the <span>following:</span>
   - add <span>LIBDIR</span> to the `<span>DYLD_LIBRARY_PATH</span><span>' environment variable
     during execution

See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
----------------------------------------------------------------------
Installing shared extensions:     /usr/lib/php/extensions/no-debug-non-zts-20100525/
andy@AndyMacBookPro:~/Downloads/php-5.4.30/ext/andy$</span></code>

We can go to this directory and see that our so extension is already here:

<code>andy<span>@AndyMacBookPro</span><span>:/usr/lib/php/extensions/no-debug-non-zts-</span><span>20100525</span><span>$ </span>ll
total <span>1440</span>
drwxr-xr-x  <span>8</span> root  wheel     <span>272</span><span>2</span><span>6</span><span>14</span><span>:</span><span>33</span> ./
drwxr-xr-x  <span>3</span> root  wheel     <span>102</span><span>1</span><span>20</span><span>2014</span> ../
-rwxr-xr-x  <span>1</span> root  wheel   <span>10496</span><span>2</span><span>6</span><span>14</span><span>:</span><span>33</span> andy.so*
-rwxr-xr-x  <span>1</span> root  wheel  <span>172732</span><span>7</span><span>23</span><span>2014</span> apc.so*
-rwxr-xr-x  <span>1</span> root  wheel   <span>51424</span><span>7</span><span>1</span><span>2014</span> mssql.so*
-rwxr-xr-x  <span>1</span> root  wheel   <span>30084</span><span>7</span><span>2</span><span>2014</span> pdo_odbc.so*
-rwxr-xr-x  <span>1</span> root  wheel  <span>255656</span><span>6</span><span>23</span><span>2014</span> redis.so*
-rwxr-xr-x  <span>1</span> root  wheel  <span>200880</span><span>9</span><span>22</span> 09<span>:</span><span>37</span> xdebug.so*
andy<span>@AndyMacBookPro</span><span>:/usr/lib/php/extensions/no-debug-non-zts-</span><span>20100525</span>$</code>

Then in the last step, we need to add the .so file we compiled to our php.ini:

extension = andy.so

Because the directory /usr/lib/php/extensions/no-debug-non-zts-20100525 is the default extension reading directory of my local PHP, there is no need to write it when configuring php.ini specific path.

Then restart apache:

apachectl restart

After that we can see that our extension has appeared in phpinfo().

Then we write a simple php script to call the extension function we wrote:

<code><php>echo andy_whoami();
<span>?></span></php></code>

You can see that it is printed out

I'm andy, It's nice to meet you. wish we could be happy together :-) The .1 after .1

is caused by RETURN_TRUE. You can remove RETURN_TRUE and the 1 will not appear.

All the above codes are referenced from: http://rango.swoole.com/archives/152. Thanks to Rango, I have my first C extension for php. This is also the simplest and most effective C extension tutorial I have ever seen. .

The above introduces the simplest C extension of PHP, including the content. I hope it will be helpful to friends who are interested in PHP tutorials.