Subject: Re: HEADS UP: migration to fully dynamic linked "base" system
To: Jason R Thorpe <thorpej@wasabisystems.com>
From: Johnny Billquist <bqt@update.uu.se>
List: current-users
Date: 08/27/2002 17:28:32
On Tue, 27 Aug 2002, Jason R Thorpe wrote:

> On Tue, Aug 27, 2002 at 02:07:45PM +0200, Johnny Billquist wrote:
> 
>  > Yes, but suppose then that /bin/ls dlopen() some other stuff, which in
>  > turn wants to access stuff in libc, and the thing dlopen():en is from an
>  > older build. It can then refer to an older version of libc than the one
>  > you statically linked in.
> 
> This is handled using shlib versioning.  You never need an "older" libc
> so long as the old one and the new one have the same major number.  So,
> if "myprog" and "foo.so" both depend on "libc.so", the single instance
> of "libc.so" used by "myprog" will always satisfy the needs of "foo.so".

[...]

So there really is no checking here. It's implicitly taken care of by the
fact that every shared object that refer to one that has it's major number
bumped should also have the major number bumped.

And you asked why I called shared libraries in Unix a hack? :-)

	Johnny

Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt@update.uu.se           ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol