function is passed no values. It's ok for the function to call
`error()` if something isn't configured right.
+### refresh
+
+ hook(type => "refresh", id => "foo", call => \&refresh);
+
+This hook is called just before ikiwiki scans the wiki for changed files.
+It's useful for plugins that need to create or modify a source page. The
+function is passed no values.
+
### needsbuild
hook(type => "needsbuild", id => "foo", call => \&needsbuild);
-This allows a plugin the manipulate the list of files that need to be
+This allows a plugin to manipulate the list of files that need to be
built when the wiki is refreshed. The function is passed a reference to an
array of pages that will be rebuilt, and can modify the array, either
adding or removing files from it.
this plugin. This is how you can add support for new and exciting markup
languages to ikiwiki.
-Note that if you choose a filename extension that starts with "_",
-ikiwiki will not render the page, or allow the page to be edited with the
-web interface. This is useful for certian types of internal-use pages, but
-should generally be avoided.
-
The function is passed named parameters: "page" and "content" and should
return the htmlized content.
Passed a page and an extension, returns the filename that page will be
rendered to.
+## Internal use pages
+
+Sometimes it's useful to put pages in the wiki without the overhead of
+having them be rendered to individual html files. Such internal use pages
+are collected together to form the RecentChanges page, for example.
+
+To make an internal use page, register a filename extension that starts
+with "_". Internal use pages cannot be edited with the web interface,
+generally shouldn't contain wikilinks or preprocessor directives (use
+either on them with extreme caution), and are not matched by regular
+PageSpecs glob patterns, but instead only by a special `internal()`
+[[ikiwiki/PageSpec]].
+
## RCS plugins
ikiwiki's support for [[revision_control_systems|rcs]] also uses pluggable