Eclipse/FAQ/buid.xml

Creating: MANIFEST.MF (right-click) > PDE Tools > Create Ant Build File

To prevent PDE from deleting your custom build.xml: MANIFEST.MF (left-click) > Build > Custom Build (check)

Executing:
 * build.xml (right-click) > Run Ant
 * (export the plug-in)
 * site.xml (left-click) > Build All