[2290] in SIPB_Linux_Development
Re: Athena RPM problems
daemon@ATHENA.MIT.EDU (Eric Mumpower)
Sun Nov 8 00:15:04 1998
Date: Sun, 8 Nov 1998 00:14:47 -0500 (EST)
To: Greg Hudson <ghudson@MIT.EDU>
Cc: amu@MIT.EDU (Aaron M. Ucko), linux-dev@MIT.EDU
In-Reply-To: <199811070037.TAA02131@small-gods.mit.edu>
From: Eric Mumpower <nocturne@cygnus.com>
> > RPM assumes that if X depends on Y and you ask it to install both at
> > the same time, the order doesn't matter.
>
> In that case, the install script for X should not assume that the
> install script for Y has already been run. It's poor to assume that
> the installer is the only path for people adding these RPMs to their
> systems, or we might as well have just used track.
This is what the "prereq:" tag (introduced in RPM v2.4.3) was created
for. From the release announcement for RPM 2.4.3:
> 2.4.2 -> 2.4.3:
> - implemented install time prerequisites
[... other features/notes elided ...]
> The most interesting of these are prerequisites and the changes to
> pre/post scripts. Package builders can now use the prereq: tag, which
> takes an argument exactly like the requires: tag. This tells RPM that
> the dependencies must be satisfied *before* this package may be installed
> and during the entire time the package is installed. So far, this is
> only enforced at install time, but it will soon be enforced at remove
> time as well.
>
> This means that RPM may now reorder it's command line arguments in order to
> satisfy dependencies! rpmlib programmers can get to this via the
> rpmdepOrder() function.
