[wp-hackers] How to Make Plugin MU-Capable

[Donncha O Caoimh]

Hi,

The main difference between WP and MU for plugins is where the plugin 
lives. There is a plugins folder still, but there's also an mu-plugins 
folder too. Any file in mu-plugins will be included/loaded on every 
request. It's likely that your plugin will be dropped in there.

Also, almost every user on an MU site is untrusted, even admins. The 
only people who should have access to edit css or html in your plugin 
are site admins. You can check if the current user is one by using the 
is_site_admin() function, any time after init.

Donncha

Jorge Peña wrote:
> Hello, I'm the developer for a plugin (wp-recaptcha) and it has been my
> intention (Due to many requests) to make it MU-capable, the only 'problem'
> is I haven't gotten around to figuring out what it is that this entails.
> 
> Does MU use actions and filters? The main filters I use are:
> 
> wp_head - CSS for the reCAPTCHA related things on the blog such as hidden
> emails (filter)