PHP啓動時配置文件顯示： Loaded Configuration File => (none)

錯誤示下：

php -i | grep Load
Loaded Configuration File => (none)
libXML Loaded Version => 20901

解決辦法：

使用strace去追蹤一下：

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

grep 'php.ini' /tmp/1.log 顯示如下信息：

open("/usr/local/php-7.0.23/bin/php-cli.ini", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/local/php/etc/php-cli.ini", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/local/php-7.0.23/bin/php.ini", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/local/php/etc/php.ini", O_RDONLY) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/local/php/etc/php.d", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)

把php.ini複製到/usr/local/php-7.0.23/bin/下，然後配置文件加載成功了。
#cp /usr/local/php-7.0.23/etc/php.ini /usr/local/php-7.0.23/bin/

注：如果編譯時指定配置文件路徑（--with-config-file-path=/usr/local/php-7.0.23/etc），PHP會先去加載指定的配置文件，如果未找到會去找默認配置文件存放路徑。