PHP开发炸鸡1（Call to undefined function pcntl_fork()）

背景：框架thinkphp5 ，php版本7.1.8，mamp

需求：结合命令行和redis，redis执行队列任务，异步发送微信公众号模板消息。
问题：在执行pcntl_fork函数时报出函数不存在的错误，由于我使用的开发环境是mamp，生成pcntl库是个漫长而且眼花缭乱的过程，于是趁着安装过程写下这片博客。
期间曾经尝试原生编译php，发现各种库缺失（mac os），于是果断放弃！重新安装mamp，最后整理这份脚本生成pcntl。
将下列脚本保存成脚本文件（.sh）并执行。

#!/usr/bin/env bash

set -xo pipefail

# Command lines tools
xcode-select --install

# Install dependencies
brew install wget autoconf openssl libjpeg libpng lzlib curl imap-uw readline postgresql libxml2 mcrypt gettext libxslt homebrew/dupes/libiconv icu4c expat bison webp freetype

# Dirs
mkdir -p /Applications/MAMP/bin/php/php7.1.8/include
cd /Applications/MAMP/bin/php/php7.1.8/include

# Download PHP 7.1.8 sources
if [ ! -f php-7.1.8.tar.bz2 ]; then
wget -q http://fr2.php.net/get/php-7.1.8.tar.bz2/from/this/mirror -O php-7.1.8.tar.bz2
fi

# Extract
if [ -f php-7.1.8.tar.bz2 ]; then
tar -xjvf php-7.1.8.tar.bz2
mv php-7.1.8 php
fi

# Configure PHP
cd /Applications/MAMP/bin/php/php7.1.8/include/php/php-7.1.8
./configure --with-gd=shared --with-jpeg-dir=/usr/local/opt/jpeg --with-png-dir=/usr/local/opt/libpng --with-zlib --with-zlib-dir=/usr/local/opt/lzlib --with-freetype-dir=/usr/local/opt/freetype --prefix=/Applications/MAMP/bin/php/php7.1.8 --exec-prefix=/Applications/MAMP/bin/php/php7.1.8 --sysconfdir=/Applications/MAMP/bin/php/php7.1.8/conf --with-config-file-path=/Applications/MAMP/bin/php/php7.1.8/conf --enable-ftp --enable-gd-native-ttf --with-bz2=/usr --with-ldap --with-mysqli=mysqlnd --enable-mbstring=all --with-curl=/usr/local/opt/curl --enable-sockets --enable-bcmath --with-imap=shared,/usr/local/opt/imap-uw --enable-soap --with-kerberos --enable-calendar --with-pgsql=shared,/usr/local/opt/postgresql --enable-exif --with-libxml-dir=/usr/local/opt/libxml2 --with-gettext=shared,/usr/local/opt/gettext --with-xsl=/usr/local/opt/libxslt --with-pdo-mysql=mysqlnd --with-pdo-pgsql=shared,/usr/local/opt/postgresql --with-mcrypt=shared,/usr/local/opt/mcrypt --with-openssl=/usr/local/opt/openssl --enable-zip --with-iconv=/usr/local/opt/libiconv --enable-opcache --enable-intl --with-tidy=shared --with-icu-dir=/usr/local/opt/icu4c --enable-wddx --with-libexpat-dir=/usr/local/opt/expat --with-readline=/usr/local/opt/readline --with-mhash YACC=/usr/local/opt/bison/bin/bison --with-webp-dir=/usr/local/opt/webp

# Phpize
cd /Applications/MAMP/bin/php/php7.1.8/include/php/php-7.1.8/ext/pcntl
phpize

# Build
./configure
make

# Install ext
if [ -f modules/pcntl.so ]; then
cp modules/pcntl.so /Applications/MAMP/bin/php/php7.1.8/lib/php/extensions/no-debug-non-zts-20160303/pcntl.so

cat << 'EOF' >> /Applications/MAMP/bin/php/php7.1.8/conf/php.ini
[pcntl]
extension=pcntl.so
EOF
fi

大约40～60分钟才编译完成，汗！

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

+ '[' -f modules/pcntl.so ']'
+ cp modules/pcntl.so /Applications/MAMP/bin/php/php7.1.8/lib/php/extensions/no-debug-non-zts-20160303/pcntl.so

OK，剩下的就是调用的问题了。

在php.ini文件最后加入

extension="pcntl.so"

注意，命令行和web执行时可能存在有不同的php.ini的情况，web还好说，通过phpinfo即可得知php路径。命令行下可以执行下php -i|grep php.ini 来得到ini文件的路径，如果这个路径内没有php.ini，需要copy一份或复制一份。另外还需注意的一点是，php.ini的extension_dir变量的值要保持统一，不然依然会报类似找不到库的错误，我先吐会血去。。。