sudo /usr/local/mysql/support-files/mysql.server start
#!/usr/bin/env python 防止用户没有将python装在默认的/usr/bin/路径下。系统检测这一行，env在系统目录PATH中查找python安装路径
If you have several versions of Python installed,
/usr/bin/env will ensure the interpreter used is the first one on your environment’s
$PATH. The alternative would be to hardcode something like
#!/usr/bin/python; that’s ok, but less flexible.
In Unix, an executable file that’s meant to be interpreted can indicate what interpreter to use by having a
#! at the start of the first line, followed by the interpreter (and any flags it may need).
If you’re talking about other platforms, of course, this rule does not apply (but that “shebang line” does no harm, and will help if you ever copy that script to a platform with a Unix base, such as Linux, Mac, etc).