ref:

From php5.6 to php7.0:

#Apache:
sudo a2dismod php5.6 ; sudo a2enmod php7.0 ; sudo service apache2 restart
#CLI:
sudo update-alternatives --set php /usr/bin/php7.0

From php7.0 to php5.6:

#Apache:
sudo a2dismod php7.0 ; sudo a2enmod php5.6 ; sudo service apache2 restart
#CLI:
sudo update-alternatives --set php /usr/bin/php5.6

problem may be happen in phpmyadmin, missing mbstring, solve below:

sudo apt-get install php5.6-mbstring
sudo apt-get install php5.6-mysql
sudo service apache2 restart

php安装错误 (node.c:1953:error dereferencing pointer to incomplete type) 解决办法

make: *** [ext/dom/node.lo] Error 1 在国外的一个网站上找到了这个，其他版本的php也同样适用。

 curl -o php-5.x.x.patch https://mail.gnome.org/archives/xml/2012-August/txtbgxGXAvz4N.txt
 cd php-5.x.x
 patch -p0 -b < ./php-5.x.x.patch 

#   patching file ext/dom/node.c

#   patching file 

#   ext/dom/documenttype.c

#   patching file ext/simplexml/simplexml.c

再次编译即可。

php.ini Loaded Configuration File :none 觖決方法

在linux下可以使用bash命令脚本：

sudo find / -name 'php.ini'

实在没有办法，只能使用strace去追踪一下：

strace  /usr/local/php/bin/php -i 2> /tmp/1.log

此时，发现问题，php竟然去/usr/local/php/bin/ 下去找php.ini了。

php.ini default timezone

date.timezone=Asia/Hong_Kong

self compile php configure file

## omited 
#--with-mysqli= /etc/mysql/my.cnf \
#--with-openssl=/usr/local2/ \
#--with-iconv=/usr/local \
#--with-ttf \
#--with-xpm \
#--with-xml \
#--enable-track-vars \
#--enable-memory-limit \



sudo ./configure \
--prefix=/usr/local/php55329 \
--with-config-file-path=/usr/local/php55329/etc \
--with-apxs2 \
--with-curl=/usr/local/lib \
--with-gd \
--enable-gd-native-ttf \
--with-gettext \
--with-jpeg-dir=/usr/local/lib \
--with-freetype-dir=/usr/local/lib \
--with-kerberos \
--with-mcrypt \
--with-mhash \
--with-mysql=/usr/bin/mysql \
--with-pdo-mysql \
--with-pear \
--with-png-dir=/usr/local/lib \
--with-zlib \
--with-zlib-dir=/usr/local/lib \
--enable-zip \
--enable-bcmath \
--enable-calendar \
--enable-ftp \
--enable-magic-quotes \
--enable-sockets \
--enable-mbstring \
--enable-mbregex \
--enable-exif \
--disable-ipv6 \
--with-imap=/usr/local/imap-2007 \
--with-imap-ssl \
--enable-soap