[gentoo-dev] Re: "Conflicts" [was -Re: Suggestion for new dependency syntax-]

[Jon Nelson]

On Fri, 26 Oct 2001 18:10:10 +0200 (CEST)
"Tom von Schwerdtner" <tvon@×××××.org> wrote:

> > Instead of using ! why not add a CONFLICTS = " foo bar baz " line.
> > Debian has Conflicts, Requires, Suggests and a few others.
> > RedHat has Conflicts, Requires, PreRequires etc..
> > ("it" below refers to the dependency)
> > Requires means it is required to *run*
> > PreRequires means it must be installed and config'd for the package
> >   to install
>
> Debian's "conflicts" are only conflicts in the sense that the Debian
> package management system (or practices) make it so.  There is no reason
> why you cant have 4 httpd servers and every DBMS on the planet installed
> on your system.  Granted, in most cases you only need one httpd server
> or
> one DBMS, but you shouldnt need to work around the package mangement
> system to get what you want.

Debian's "conflicts" don't prevent more than 1 httpd from being
installed -- they prevent a case like this:

Package: foo
Conflicts: bar

Package: bar
<notice, no Conflicts line>

You install foo, then want to install bar.
it would complain, saying, "hey, you can't do that without
damaging the install of foo!"

You install bar, and want to install foo.
...

Conflicts are more useful when two packages really do conflict,
not at the purpose level, but at the filesystem level.

Which reminds me.  On my Debian box, I can install
gcc-2.95.X *and* gcc-3.0 and both are available and both
are seperate.  I choose which I want to use by calling
either gcc (gcc-2.95.X) or gcc-3.0 (gcc-3.0), something that
can often be set in configure scripts like this:

CC=gcc-3.0 ./configure


-- 
Jon Nelson
jnelson@×××××××.net
C and Python Programmer
Motorcycle Enthusiast