>What is the legal position as reguards software reuse. I know a number of U.S.
>departments actively encourage the production of reusable software. If this
>results in a library of reusable generic components are these component covered
>by copyright when modified to transfer the technology to another domain. Likewise is public domain software like the ANDREW TOOLKIT covered by copyright
>when the function calls are included within a client program produced by another party.
Copying is copying. In the United States, since we joined Berne,
copyright protection is automatic - it is by operation of law.
You don't have to do anything to get copyright protection.
(but you do have to register before you can sue).
This means that any software written, unless written by Federal Govt employees
is automatically protected by copyright.
Once we have determined that C/R law applies, we have to ask whether you
can use it. If the author placed the software in a library of resuable
software, I would argue that he agreed to a non-exclusive license thereof.
Non-exclusive licenses don't have to be in writing, nor do they have to
be recorded to be effective.
One corrolary to the above is that works only enter the public domain
when donated thereto by an affirmative act (with the Fed Govt exception
noted above). It is no longer automatic.
That said, if the above referenced software is truley in the public
domain, then it can be freely copied, in whole or in part (including
one module). That is of course assuming that the public domain work
doesn't contain modules that are not in the public domain (i.e. the
program itself (including the organization of the modules) has been
dedicated to the public, but one or more of the modules were written
by someone else - remember what is in the public domain tracks exactly
someone's copyright rights at some point in time).
Note - this analysis was done for U.S. law, which I am familiar with.
It is at best only suggestive if what you are interested in is U.K. law.
