The registry maintains a database of persistent settings for an
application. The settings database is organized in two groups of three
layers each. The system-wide settings group contains settings information
pertaining to all users on a system. The per-user settings group contains
settings affecting that user only. Each settings group contains a desktop
layer, which comprises the settings which affect all FOX programs, a vendor
layer which holds settings that affect all applications from that vendor
(e.g. a application-suite), and an application layer which holds settings
only for a single application. The vendor-key and application-key determine
which files these layers come from, while the "Desktop" key is
used for all FOX applications. Settings in the system-wide group are
overwritten by the per-user group, and settings from the
"Desktop" layer are overwritten by the vendor-layer; vendor-layer
settings are overwritten by the application-layer settings. Only the
per-user, per-application settings ever gets written; the layers in the
system-group only get written during installation and configuration of the
application. The registry is read
when FXApp::init() is called, and written back to the system when
FXApp::exit() is called.