Re: Tomato, tomahto
Hi Lorna - Yes, and no. Let's start with no -- the API spec is the API spec much like Ethernet is Ethernet. Extending the API basically makes you incompatible so unless you can get the market accept your changes (either through market share or future versions of the standard) you're out of luck. The yes side is that once you get a call, you can be creative which could mean additional configuration that is outside of the scope of the standard.
For example, the way that you read/write files from Unix has a standard API set by POSIX eons ago. Follow the API, and your application will work across multiple flavors of Unix without issue. Each flavor of Unix then offered up their own flavor of interpreting the API by creating different filesystems with different performance and resiliancy characteristics. The first vendor to create a filesystem that could handle a hard shutdown without needing to run a repair process on the next boot (IBM with JFS, if I recall correctly) had a differentiation even though they tied into the same POSIX API.