What ever happened to Tandem and NonStop OS 2123

In Win3.1 the first loaded .dll of a given filename was used by all later apps looking for that named .dll- even if it was the wrong version. So if app X loads before app Y, Y would crash whereas if Y was loaded first X would run. LOTS of system management effort went into finding combinations of .dlls what would allow apps to run properly- until the next upgrade or new install broke things again.

Win32 used the pathname of the .dll to distinquish between .dll's, so app X and app Y could load different versions of the same .dll by virtue of installing their preferred copy in the apps install directory. Somewhat better, but even today theres still nothing to stop an install program from stomping on OS core .dll's and messing up (or even killing) the entire OS. Pretty much the only thing saving Windows users is the fact that most apps don't bring along system .dlls- but all it takes is a poorly constructed install program.

Probably the same old problem. Linux hedges its bets by allowing apps to specify particular shared libraries in leu of the default system ones- but since things are so often compiled from source, the problem is fundamentally less pernicious.

Gregm