morphos vs amiga os4

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@KennyR:

Of course. AmigaOS4 is not a memory protected system, and never can be if you want to run Amiga apps on it. Unless you go the sandbox route, that is, which MOS has already done.

If I remember correctly, their mmu system is used to protect the kernel space, so you may crash apps but you won't be able to write in the kernel space... anyway, in MorphOS as most of OS components run inside the A-Box, you can crash everything in the Abox because the Exec kernel memory zone is not protected as in OS4... at least I have crashed MorphOS and the Q-Box was pretty useless because almost everything runs inside the A-Box...
I'm not stating that one approach is superior to the other, I think that both have their advantages... in the future MorphOS will have more components moved to the Q-Box and it may work better... but if OS4 protects the kernel and some basic drivers from being written by other apps, OS4 should be SLIGHTLY more stable when running 3.x apps. Only SLIGHTLY. Native OS4 apps will probably run using their memory system... let's hope it doesn't break compatibility much. And native Q-Box apps will run in a protected environment too, so new apps for both systems should run pretty stable (that excludes new morphOS apps that uses the A-Box due to the environment they are working...)
Feel free to correct me... but I'm pretty sure that if I recompile a 3.x apps for the A-Box it won't be memory protected... with OS4 the old 3.x app should have memory protection...
Correct me if I'm wrong but don't be too rude ;-)

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@zacman:
sorry, but I edited the mail after posting because I knew that someone would say that...
Almost everything runs in the A-Box, including the A-Box replacement of the Exec that acts as the "kernel" of the A-Box... so if I crash that "kernel" or better said, the exec.library (I know that the MorphOS kernel is Quarx) all the A-Box will crash as in 3.x. And in the current state of MorphOS most of the system components run in the A-Box, so they are affected by that crash, and you end up resetting your computer as in 3.x. With Pure Q-Box apps it shouldn't happen, but with new apps if they run inside the A-Box you will always have an insecure environment (yeah, insecure inside the A-Box, the Q-Box stuff shouldn't freeze, but if you run even some drivers in the A-Box, the Q-Box concept isn't used to the max and you and up with a very fast 3.x system, but little more)

>with OS4 the old 3.x app should have memory
>protection...

No they won't. That's why it is called "optional
memory protection" in OS4.

that's why I said that an app would have memory protection RECOMPILING the app for OS4, not running it directly without modifications.

But this is of course speculation, I can't say much about this until I see the SDK... and depending on how the app is coded you may have to change the sources... we'll have to wait and see.

On the other hand I have to say that although memory protection is an important feature for a new OS, if the apps the user wants to run are well coded he shouldn't need it... in AmigaOS3.x you can see fast if an App is well coded or not :-)