Re: dep-trace v. tsort (dpkg, source, bsd, reason)

["John D. Hendrickson and Sara Darnell" <johnandsara2@cox.net>]

Thanks !  I'm sure someone "is aware" :)  Was not sure it posted.

Correct and yes your right, but not "optimal".  Let's say apt selected this depends list:

A
B C
D

All satisfied as a list to install, yes.  Should work, the book says.

But if installed in order "C B D A" it may cause headaches (see below).

If optionally applied in order "A B C D", sorted by deps, success is more likely.

If ever you need "low level" depends sorter you'll know one exists, have one to look at or compare to.

Have a good day thanks much for the question,

	John


#### examples #####

	#0  I see many avoid using Pre-Depends, as it's "strict", when they could
	    and the rules suggest not to use Pre-Depends without permission ?

	#1  if C is alpha and made some assumption about B already existing
	    if running system / user tries using C before B is ready

	#2  if install stops (ie, Ctrl-C) and system breaks until corrected
	    (ex: C is an admin util, B is perl, to run C to get work done
		 you need both B C installed, but your power got shut off after
		 400 pkgs, leaving you with C but not B and maybe both broken)

	#3  once a break happens there "are no rules" per say and both may have
	    difficulties installing after that

	These kinds of things can be frustrating and time consuming.
	The longer the install list, the more chance of mistakes or partial install.

##### in a 90's release, "buzz", install guide called lack of order "a bit loopy"