DRYOS is an embedded real-time operating system developed by Canon for use in compact devices and employed in a wide range of company products such as digital cameras and digital video camcorders.
Source: Canon Inc.
“Since late 2007 Digic-based cameras are shipped using Canon's own Operating System named DryOS...DryOS Porting
“DryOS Shell is available via UART Serial Connection with Camera. On Camera Startup the Canon...DryOS Shell
“Canons firmware includes a scripting language, which appears to be a flavor of basic. Thanks to...Canon Basic/Reference