1. 发现运行php 的interactive shell 的时候，不能输入一行执行一行，而要 输入完一整段内容，再按 ctrl + d才能执行这段内容。
原因是，没安装 readline这个模块，
有安装readline就可以
http://php.net/manual/en/features.commandline.interactive.php
https://stackoverflow.com/questions/14792842/how-does-the-interactive-php-shell-work
Interactive Shell and Interactive Mode are not the same thing, despite the similar names and functionality.
If you type 'php -a' and get a response of 'Interactive Shell' followed by a 'php>' prompt, you have interactive shell available (PHP was compiled with readline support). If instead you get a response of 'Interactive mode enabled', you DO NOT have interactive shell available and this article does not apply to you.
You can also check 'php -m' and see if readline is listed in the output - if not, you don't have interactive shell.
Interactive mode is essentially like running php with stdin as the file input. You just type code, and when you're done (Ctrl-D), php executes whatever you typed as if it were a normal PHP (PHTML) file - hence you start in interactive mode with '<?php' in order to execute code.