HALs considered harmful
Posted Mar 17, 2005 12:40 UTC (Thu) by sdalley
Parent article: HALs considered harmful
Although it might have been gone over "a thousand times before" I am totally at a loss to understand this reasoning.
It is *sometimes* necessary to program as close to the metal as possible for reasons of speed. However, for reasons of maintainability, it always makes sense to do what is called "information hiding", i.e. to hide the specifics of the OS-specific interfaces in one place under more generic wrappers, and call those wrappers from the device-specific stuff. This does not just make things easier for the vendor to target multiple OSes, it also localises the linux-kernel interface calls in a small area, typically one file. The kernel maintainers then have only one file to worry about when the inevitable function call interface changes occur.
Done right, it should make the kernel maintainer's job easier as well as the vendor's job. What am I missing here ? (scratches head).
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