參考：http://www.cnblogs.com/yjf512/p/3217615.html

還是老三樣：phpize, ./configure, make && make install

當然是要到你下載的php原始碼的ext目錄中執行。

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ phpize

Configuring for:

PHP Api Version:         20100412

Zend Module Api No:      20100525

Zend Extension Api No:   220100525

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ ./configure 

checking for grep that handles long lines and -e... /usr/bin/grep

checking for egrep... /usr/bin/grep -E

checking for a sed that does not truncate output... /usr/bin/sed

checking for cc... cc

checking whether the C compiler works... yes

checking for C compiler default output file name... a.out

checking for suffix of executables... 

checking whether we are cross compiling... no

checking for suffix of object files... o

checking whether we are using the GNU C compiler... yes

checking whether cc accepts -g... yes

checking for cc option to accept ISO C89... none needed

checking how to run the C preprocessor... cc -E

checking for icc... no

checking for suncc... no

checking whether cc understands -c and -o together... yes

checking for system library directory... lib

checking if compiler supports -R... no

checking if compiler supports -Wl,-rpath,... yes

checking build system type... i386-apple-darwin13.4.0

checking host system type... i386-apple-darwin13.4.0

checking target system type... i386-apple-darwin13.4.0

checking for PHP prefix... /usr

checking for PHP includes... -I/usr/include/php -I/usr/include/php/main -I/usr/include/php/TSRM -I/usr/include/php/Zend -I/usr/include/php/ext -I/usr/include/php/ext/date/lib

checking for PHP extension directory... /usr/lib/php/extensions/no-debug-non-zts-20100525

checking for PHP installed headers prefix... /usr/include/php

checking if debug is enabled... no

checking if zts is enabled... no

checking for re2c... no

configure: WARNING: You will need re2c 0.13.4 or later if you want to regenerate PHP parsers.

checking for gawk... no

checking for nawk... no

checking for awk... awk

checking if awk is broken... no

checking whether to enable pcntl support... yes, shared

checking for fork... yes

checking for waitpid... yes

checking for sigaction... yes

checking for getpriority... yes

checking for setpriority... yes

checking for wait3... yes

checking for sigprocmask... yes

checking for sigwaitinfo... no

checking for sigtimedwait... no

checking for ld used by cc... /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld

checking if the linker (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld) is GNU ld... no

checking for /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld option to reload object files... -r

checking for BSD-compatible nm... /usr/bin/nm

checking whether ln -s works... yes

checking how to recognize dependent libraries... pass_all

checking for ANSI C header files... yes

checking for sys/types.h... yes

checking for sys/stat.h... yes

checking for stdlib.h... yes

checking for string.h... yes

checking for memory.h... yes

checking for strings.h... yes

checking for inttypes.h... yes

checking for stdint.h... yes

checking for unistd.h... yes

checking dlfcn.h usability... yes

checking dlfcn.h presence... yes

checking for dlfcn.h... yes

checking the maximum length of command line arguments... 196608

checking command to parse /usr/bin/nm output from cc object... ok

checking for objdir... .libs

checking for ar... ar

checking for ranlib... ranlib

checking for strip... strip

checking for dsymutil... dsymutil

checking for nmedit... nmedit

checking for -single_module linker flag... yes

checking for -exported_symbols_list linker flag... yes

checking if cc supports -fno-rtti -fno-exceptions... yes

checking for cc option to produce PIC... -fno-common

checking if cc PIC flag -fno-common works... yes

checking if cc static flag -static works... no

checking if cc supports -c -o file.o... yes

checking whether the cc linker (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld) supports shared libraries... yes

checking dynamic linker characteristics... darwin13.4.0 dyld

checking how to hardcode library paths into programs... immediate

checking whether stripping libraries is possible... yes

checking if libtool supports shared libraries... yes

checking whether to build shared libraries... yes

checking whether to build static libraries... no

creating libtool

appending configuration tag "CXX" to libtool

configure: creating ./config.status

config.status: creating config.h

config.status: config.h is unchanged

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ make && make install

/bin/sh /Users/andy/Downloads/php-5.4.30/ext/pcntl/libtool --mode=install cp ./pcntl.la /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules

cp ./.libs/pcntl.so /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules/pcntl.so

cp ./.libs/pcntl.lai /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules/pcntl.la

----------------------------------------------------------------------

Libraries have been installed in:

   /Users/andy/Downloads/php-5.4.30/ext/pcntl/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'

flag during linking and do at least one of the following:

   - add LIBDIR to the `DYLD_LIBRARY_PATH' 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.

----------------------------------------------------------------------

Build complete.

Don't forget to run 'make test'.

Installing shared extensions:     /usr/lib/php/extensions/no-debug-non-zts-20100525/

cp: /usr/lib/php/extensions/no-debug-non-zts-20100525/#[email protected]#: Permission denied

make: *** [install-modules] Error 1

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ php -m

[PHP Modules]

andy

bcmath

bz2

calendar

Core

ctype

curl

date

dba

dom

ereg

exif

fileinfo

filter

ftp

gd

hash

iconv

json

ldap

libxml

mbstring

mssql

mysql

mysqli

mysqlnd

openssl

pcre

PDO

pdo_dblib

pdo_mysql

PDO_ODBC

pdo_sqlite

Phar

posix

readline

redis

Reflection

session

shmop

SimpleXML

snmp

soap

sockets

SPL

sqlite3

standard

sysvmsg

sysvsem

sysvshm

tidy

tokenizer

wddx

xdebug

xml

xmlreader

xmlrpc

xmlwriter

xsl

zip

zlib

[Zend Modules]

Xdebug

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ vim /private/etc/php.ini

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ sudo vim /private/etc/php.ini

Password:

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ php -m

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/extensions/no-debug-non-zts-20100525/pcntl' - dlopen(/usr/lib/php/extensions/no-debug-non-zts-20100525/pcntl, 9): image not found in Unknown on line 0

[PHP Modules]

andy

bcmath

bz2

calendar

Core

ctype

curl

date

dba

dom

ereg

exif

fileinfo

filter

ftp

gd

hash

iconv

json

ldap

libxml

mbstring

mssql

mysql

mysqli

mysqlnd

openssl

pcre

PDO

pdo_dblib

pdo_mysql

PDO_ODBC

pdo_sqlite

Phar

posix

readline

redis

Reflection

session

shmop

SimpleXML

snmp

soap

sockets

SPL

sqlite3

standard

sysvmsg

sysvsem

sysvshm

tidy

tokenizer

wddx

xdebug

xml

xmlreader

xmlrpc

xmlwriter

xsl

zip

zlib

[Zend Modules]

Xdebug

我們看到擴充套件了還是沒有pcntl擴充套件，可以看到上面有一個cp的error，所以我們sudo一下：

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ sudo make

/bin/sh /Users/andy/Downloads/php-5.4.30/ext/pcntl/libtool --mode=install cp ./pcntl.la /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules

cp ./.libs/pcntl.so /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules/pcntl.so

cp ./.libs/pcntl.lai /Users/andy/Downloads/php-5.4.30/ext/pcntl/modules/pcntl.la

----------------------------------------------------------------------

Libraries have been installed in:

   /Users/andy/Downloads/php-5.4.30/ext/pcntl/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'

flag during linking and do at least one of the following:

   - add LIBDIR to the `DYLD_LIBRARY_PATH' 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.

----------------------------------------------------------------------

Build complete.

Don't forget to run 'make test'.

[email protected]:~/Downloads/php-5.4.30/ext/pcntl$ sudo make install

Installing shared extensions:     /usr/lib/php/extensions/no-debug-non-zts-20100525/

[email protected]:/usr/lib/php/extensions/no-debug-non-zts-20100525$ php -m

[PHP Modules]

andy

bcmath

bz2

calendar

Core

ctype

curl

date

dba

dom

ereg

exif

fileinfo

filter

ftp

gd

hash

iconv

json

ldap

libxml

mbstring

mssql

mysql

mysqli

mysqlnd

openssl

pcntl

pcre

PDO

pdo_dblib

pdo_mysql

PDO_ODBC

pdo_sqlite

Phar

posix

readline

redis

Reflection

session

shmop

SimpleXML

snmp

soap

sockets

SPL

sqlite3

standard

sysvmsg

sysvsem

sysvshm

tidy

tokenizer

wddx

xdebug

xml

xmlreader

xmlrpc

xmlwriter

xsl

zip

zlib

[Zend Modules]

Xdebug

[email protected]:/usr/lib/php/extensions/no-debug-non-zts-20100525$ 

好了。

下面可以寫個示例試試：

for($x = 1;$x<= 2;$x++){
        $pid[$x] = pcntl_fork();
        if ($pid[$x] == -1) {
                die("could not fork");
        } elseif ($pid[$x]) {
                echo "Parent: create ".$pid[$x]."n";
        } else {
                        echo "fork ".getmypid()." start:n";
                        for($i = 0;$i<10;$i++){
                                echo $x.": ".$i."n";
                                sleep(1);
                        }
                exit;
        }
}

輸出結果是這樣的：

[email protected]:/usr/local/webdata/andy/php/pcntl$ php pcntl_demo.php 

Parent: create 3641

Parent: create 3642

fork 3641 start:

1: 0

fork 3642 start:

2: 0

[email protected]:/usr/local/webdata/andy/php/pcntl$ 1: 1

2: 1

1: 2

2: 2

1: 3

2: 3

1: 4

2: 4

2: 5

1: 5

1: 6

2: 6

1: 7

2: 7

1: 8

2: 8

1: 9

2: 9

[email protected]:/usr/local/webdata/andy/php/pcntl$ 

這個時候我們去ps -ef|grep php的話，可以看到有兩個php程序：

如果我們改一下程式碼，加上19行後面的程式碼：

<?php

for($x = 1;$x<= 2;$x++){
        $pid[$x] = pcntl_fork();
        if ($pid[$x] == -1) {
                die("could not fork");
        } elseif ($pid[$x]) {
                echo "Parent: create ".$pid[$x]."\n";
        } else {
                        echo "fork ".getmypid()." start:\n";
                        for($i = 0;$i<10;$i++){
                                echo $x.": ".$i."\n";
                                sleep(1);
                        }
                exit;
        }
}

while(count($pid) > 0){
	$myId = pcntl_waitpid(-1, $status, WNOHANG);
	foreach($pid as $k => $v){
		if($myId == $v) unset($pid[$k]);
	}
	usleep(100);
}



?>

可能有人會問WNOHANG是什麼意思，W NO HANG，也就是wait no hang，不阻塞的意思。

這個時候我們再執行，可以看到有三個php程序，最後一個php程序其實就是最開始的主程序，本來如果沒有加上的後面這段，主程序例項化出來兩個子程序之後就退出了，但是加上了這段，就會讓主程序等待所有子程序都結束之後，再結束自己。