On 14 Apr 2007, at 22:38, Rick Chagouri-Brindle wrote: > >> You misunderstand the concept here. Operating systems move on and >> become >> more sophisticated. Most good ones move the software writers along >> with >> them. The users buy new versions which take advantage of the new >> facilities and the whole system moves forward. >> >> If you continually make the whole thing backwardly compatible people >> carry on using the old versions and nothing advances. This is the >> state >> we have arrived at. Some new features never get used which is both a >> shame and a rebuff for those who worked on the newer ideas. We >> need to >> move forwards. >> > Indeed, at some point an Operating System - like any other application > or process - will lose some elements of its compatibility with earlier > version/environments. It is simply the nature of how progress is > made.
I personally am very pleased with the way SMSQE contains advances such as GD2 colours while still allowing the old colour system to work. My program TurboPTR, which produces windows for PE programs was amended to allow the new system to be used. It now will work either with mode 4 or the GD2 modes. Obviously programs have to be changed to use new facilities. One change I noticed which did stop some programs working related to free space. This required a change in The Editor for example. But this was minor. Another change, a long time ago, caused Perfection to stop in certain cases. This was traced to a faulty assumption in Perfection about register usage in one of the traps. The altered version of the OS was quite correct but set a different value in a register marked as "not preserved". Obviously such occurrences must be regarded as latent errors in the program, not incompatible changes in the OS. George _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
