Subject: Re: RFC: migration to a fully dynamically linked system
To: Luke Mewburn <>
From: Giles Lean <>
List: tech-userlevel
Date: 12/22/2001 10:38:51
Luke Mewburn wrote:

>   3. Dynamically link everything against /lib
>      ...
> 	Cons:
> 		- adds about 3 MB to / on an i386; the savings gained
> 		  by dynamic linking /bin and /sbin offset by the cost
> 		  of moving /usr/lib/*.so*

Space used on / could be expected to increase on each OS upgrade in
this scenario, due to the need to keep old shared library versions.
Presently all the binaries on / are replaced when the OS is upgraded,
and the old versions are not kept so disk space increase in / is

This would effect option #4 as well, unless option #4 moved old
shared libraries to /usr/lib, which I don't recommend.

>   5. Install dynamic versions of /{,s}bin programs into /usr/{,s}bin
>      ...
> 	/{,s}bin contains the `minimalist' versions of applications,
> 	and /usr/{,s}bin contains the versions that support the full
> 	range of dynamic nsswitch (et al) functionality.
>       ...
> 	Cons:
> 		- lots of user confusion

Prior art exists in HP-UX where some binaries in /sbin are duplicated
in /usr/{,s}bin.  It does cause confusion, although I don't think it
amount to "lots". The classic support call is about passwd(1).