What does PURE mean in startup assigns?

[Piru]

To be more precise, any const data, be it static or not, is ok, as long as it's not put in the BSS section.

Well naturally. That "static const" was about the specific case when static is ok.

Pure executables are also about saving memory, as you don't have to load the TEXT part of the program more than once in memory, much like libraries.

True. However, residents also waste memory. If the particular program is not running, it still sits in the memory eating chunk of memory for nothing.

In fact, not many programs really run simultanously often enough to justify being resident in memory.

The most benefit from resident commands comes with slow media (floppies, cd-rom etc).

[lurkist]

I thought the point of having something resident was not if it was run simutaneously, but if it was run multiple times  to prevent multiple accesses of the same sector on hard drives (or floppies).  For instance,  copying a large amount of files.  Sure you could use a multi-select option or something, but if you're not the disk is accessing the "copy" file each time, thus wearing it out.

That and the speed increase of course.

Or have I misunderstood the purpose of Resident?

[Piru]

The reason resident is used in startup-sequence is to speed up the booting (esp with floppies).

Not accessing the disk is the result, but the motivation wasn't reducing disk access to avoid media wearing. Naturally this might have been someone else's motivation for using residents...

[DonnyEMU]

It also means the code is able to be resident because it is RE-ENTRANT. Meaning you call call it multiple times using the same memory allocation etc.. (well not exactly but that's the general IDEA)..