arg agin shr libs

[laura at utcsstat.UUCP]

Gary, 
	your conversion of the argument against shared libraries
into an argument for shared libraries does not correspond to the activities
of people I know. I have several programs in my bin that I have not
used for years. I keep them around because, although I may never need
a program that (say) reads a tape that has bad blocks on it, if I ever do,
I will need it *immediately*. The last thing that I need is to discover
that 2 years ago, when the specifications for function X in <stdio.h>
changed, I ought to have changed my program. It would literally take
me hours to check every program I own every time there is a change...

	About a year ago, utzoo got a floating point processor, which
trapped on divide by zero, as opposed to the software simulation which
set the result to zero. Last week, I was at zoo, collecting Henry
Spencer for dinner when someone walked in with a program that had
'stopped working'. Guess what was wrong with it! I believe that in
ten years there will *still* be people who are discovering that
their programs 'suddenly do not work'.

Shared libraries seem like a good idea for *certain libraries* some of the
time. This does not make them a good idea for *all libraries* all of the
time (which some people I know believe). If shared libraries become
common in UNIX, which will probably depend on what hardware most
UNIX systems are on, (dynamic linking on a pdp-11 is hard, on a
NS16032-based machine is relatively easy, and I dont know about a
68000-based machine) someone is going to have to bite the bullet and
put 'version numbers' into the shared libraries. If we end up with
VMS style version numbers, I know many people, including myself, who
will quit doing systems programming on UNIX and find something else
to do with the rest of our lives.

laura creighton
utzoo!utcsstat!laura