使用命令进行安装：
pecl install swoole
pecl install --configureoptions 'enable-sockets="no" enable-openssl="yes" enable-http2="yes" enable-mysqlnd="yes" enable-swoole-json="no" enable-swoole-curl="yes" enable-cares="yes"' swoole
在使用 pecl 进行安装时有几个问答选项
enable sockets supports? [no] :
enable openssl support? [no] : yes
enable mysqlnd support? [no] :
enable curl support? [no] : yes
enable cares support? [no] :
enable brotli support? [yes] :
这些是用于开启某些特性，比如 openssl 是来启用 SSL 支持，大多数新手在这里都会选择 yes，之后就开始编译了
结果发现报错了：error "Enable openssl support, require openssl library."（具体的错误信息就不详细写了，大概是这样）意思就是说你开启 openssl，常规路径下没有找到，需要你手动指定 openssl 库的路径
或者fatal error: 'openssl/ssl.h' file not found
这个意思是你没有加 openssl 库的路径或者指定 openssl 库的路径不对，缺少头文件
那么在 pecl 安装的时候怎么开启添加这个路径呢？不是只能 yes 或者 no 吗？
答案是当然可以添加的，我们可以在 yes 后面跟上路径参数: --with-openssl-dir=/opt/openssl/，替换为你的 openssl 库路径
就是这样的：
enable sockets supports? [no] : yes
enable openssl support? [no] : yes --with-openssl-dir=/usr/include/openssl
enable http2 support? [no] : no
enable mysqlnd support? [no] : yes
下面我们就可以看到我们的编译参数：
building in /tmp/pear/temp/pear-build-rootVseYYu/swoole-4.4.8
running: /tmp/pear/temp/swoole/configure --with-php-config=/usr/local/php/bin/php-config --enable-sockets=yes --enable-openssl=yes --with-openssl-dir=/usr/include/openssl --enable-http2=no --enable-mysqlnd=yes
这样编译完成后就可以了
# php --ri swoole
swoole
Swoole => enabled
Author => Swoole Team
Version => 4.4.8
Built => Oct 17 2019 11:18:01
coroutine => enabled
epoll => enabled
eventfd => enabled
signalfd => enabled
cpu_affinity => enabled
spinlock => enabled
rwlock => enabled
sockets => enabled
openssl => OpenSSL 1.0.2k-fips 26 Jan 2017
http2 => enabled
pcre => enabled
zlib => enabled
mutex_timedlock => enabled
pthread_barrier => enabled
futex => enabled
mysqlnd => enabled
async_redis => enabled
Directive => Local Value => Master Value
swoole.enable_coroutine => On => On
swoole.enable_library => On => On
swoole.enable_preemptive_scheduler => Off => Off
swoole.display_errors => On => On
swoole.use_shortname => On => On
swoole.unixsock_buffer_size => 8388608 => 8388608
