[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: User's thoughts about LPPL



Steve Langasek writes:
 > On Sun, Jul 21, 2002 at 01:29:36AM +0200, Frank Mittelbach wrote:
 > > Thomas Bushnell, BSG writes:
 > 
 > >  > Indeed, I can do two things:
 > 
 > >  > Make a derivate work of latex, which is variant, and called
 > >  > "special-non-latex".  
 > 
 > >  > Make a package with no derivatives of latex at all, which contains a
 > >  > single symlink: 'latex -> special-non-latex'.
 > 
 > >  > Happy with that?
 > 
 > > yes.
 > 
 > > for the kernel it is a bit tricky, but for packages under LPPL (and the
 > > majority of software which was put by their authors under LPPL) it is not a
 > > problem.
 > 
 > > the moment somebody has a document that loads your fudged package into LaTeX ,
 > > LaTeX will detect that you are trying to sail under a stolen flag and that is
 > > the whole purpose. 
 > 
 > Are you using the word 'package' here in the same sense as Thomas?

clash of meanings for names :-) I was talking of "packages in the LaTeX sense"
not of packaged works by Debian.

 > AIUI, Thomas is referring to creating a Debian package -- not a TeX
 > package -- that is called 'latex' and which provides a mechanism (a
 > symlink or an execve hack) for directly invoking his
 > modified-and-renamed version of LaTeX by the original name.  Would LaTeX
 > really be able to detect this subterfuge?

no LaTeX would not, but "LaTeX" wouldn't be involved in this example.

by producing "special-non-latex" you are required to change its identifaction
strings which means that this program will identify itself to the user as
"not-latex" no matter what it is called as a debian package. Of course by
packaging it with a different name and/or on operating level symlinking it to
some other name you can clearly try to (and probably succeed in several case)
confuse your users (receivers of your Debian packages) that they run "latex"
as it would run on other machines.

but if the user calls 

 latex foo.tex

he would then see "This is special-non-latex version xyz" on the terminal.
Not perfect but there you are. And if this Debian package also provides a
special terminal driver that whenever it sees the string "special-non-latex"
replaces it with LaTeX2e then the fudging will be even more difficult to
detect ... yes i agree there are always ways to fudge

but back to what i was referring to as a package: a LaTeX work like
"geometry.sty". such a work is usable within LaTeX by loading it. There
symlinking isn't working, though Alexander Cherepanov correctly pointed out
that with enough energy you can built wrappers within LaTeX to make it go
undetected by the standard mechanisms and becomes visible only by explicitly
looking through LaTeX log files.

Walter, i think, asked if one can't remove that checking code through another
(independent) modification. The answer is yes, easily, but only by either

 - forking the latex kernel, ie running on a non-latex in which this whole
   discussion is irrelevent because users starting with such a kernel know
   that they can't expect their documents to behave same as if run under the
   latex kernel, or by

 -  loading a package into the document that does this change to the kernel in
    which case they know it as well.

btw, would it be acceptable to you if LPPL would say,

 in case of modification you either

  - do what LPPL asks for now (i.e. rename ...), or

  - you keep the LaTeX package file name but replace

\ProvidesPackage{varioref}
    [2000/08/22 v1.2g package for extended references (FMi)]

   by

\ProvidesModifiedPackage{varioref}
    [2000/08/22 <your versioning info>]
    [2000/08/22 v1.2g package for extended references (FMi)]   % that's the  derived info

frank


-- 
To UNSUBSCRIBE, email to debian-legal-request@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org



Reply to: