In meeting the cross-platform goals of the CPADS specification, the .APP sub-specification was identified as a solution to attain true multi-platform capability. The structure of the .APP virtual application is similar in nature to Sun Microsystem's JAR file format, where all the necessary files for execution are contained in a single compressed archive.
The structure of a .APP archive is comprised of:
- A binary virtual machine executable file (.bin)
- A virtual machine configuration settings file (.cfg)
- An Icon file for graphical execution environments (.ico)
- A (optional) help, licensing and documentation file (.doc)
- An archive manifest file which lists all files in the (optional) resource subdirectory (.rsc)
- An (optional) resource subdirectory (.rsc/)
Note: The structure of this is still under development and may or may not be representative of the final product. Extensions presented may or may not be comparable to existing standards.
Loading & Execution
Upon being loaded, the archive is inflated into memory using an as-yet unspecified algorithm, and the AVM binary is loaded into the simulated memory space according to parameters set within an internal metadata file (.cfg). If the execution environment is graphical, the AVM will setup the output window according to specified metadata.
Upon completion of the application, the residual files and folders created during the initialization process are destroyed, save for debugging and error reports.