On Jul 2, 2014, at 12:59 PM, Tobias Pape <Das.Linux at gmx.de> wrote:

> Just that it is not lost,
> 
> debian provides a facility to provide normally incompatible
> binaries. (eg, different versions, different vendors)
> they call it alternatives. (See /etc/alternatives)
> 
> one example: jvm. or cc.
> on my server:
> 
> $ ls -l /usr/bin/cc
> lrwxrwxrwx 1 root root 20 Mar 19 13:10 /usr/bin/cc -> /etc/alternatives/cc
> 
> $ ls -l  /etc/alternatives/cc
> lrwxrwxrwx 1 root root 12 Mar 19 13:10 /etc/alternatives/cc -> /usr/bin/gcc
> 
> and you can select:
> $ upate-alternatives --list cc
> /usr/bin/gcc
> /usr/bin/clang
> 
> 
> That way, we could provide different squeakvm's via this tool :)

Sounds interesting. 

"The generic name is not a direct symbolic link to the selected alterna‐
       tive.  Instead, it is a symbolic link to a  name  in  the  alternatives
       directory,  which  in turn is a symbolic link to the actual file refer‐
       enced.  This is done so that the system administrator's changes can  be
       confined  within  the  /etc directory: the FHS (q.v.) gives reasons why
       this is a Good Thing."


Chris 


> Best
> 	-Tobias
> 
> 
> On 02.07.2014, at 18:27, Chris Cunnington <brasspen at gmail.com> wrote:
> 
>> I did a bit of a survey of VMs on boxes 3 and 4. [1] My aim is to upgrade box4 to the latest Cog (non-Spur) VM available. 
>> I think I can do that in box4 with no fuss, as I don't think the Interpreter VM is installed. So I don't expect a conflict. It is worth noting that some binaries are stored in /usr/local/lib and others in /usr/lib. 
>> 
>> About where to put the .deb files. I guess the proper thing is to use cogdeb.zip in /root/localbuild and then copy the deb to /root/localdeb. 
>> 
>> Chris 
>> 
>> 
>> [1]
>> 
>> BOX3 - start script used 
>> 
>> TEST FOR VERSION:
>> cogvm -version 	r2776
>> 
>> /usr/bin/cogvm
>> 
>> BINARIES AVAILABLE: 
>> /usr/lib/squeak/4.0-2776
>> /usr/local/lib/squeak/4.10.2-2793
>> /home/chrismuller/vm/lib/squeak/4.0-2761
>> /home/chrismuller/vm/lib/4.4.7-2357
>> 
>> localdebs:
>> cogvm_2776-1_i386.deb         squeakvm_20131020-1_i386.deb
>> djbdns_1.05-2_amd64.deb       squeakvm64_20131020-1_i386.deb
>> squeak-sources_4.1-1_all.deb
>> 
>> 
>> BOX3 - no start script used? 
>> 
>> TEST FOR VERSION:
>> squeak -version
>> cannot find VM to run image 'squeak' with option ''
>> 
>> BINARIES AVAILABLE:
>> /usr/local/lib/squeak/4.10.2-2793/squeakvm
>> /home/davidlewis/[VM|VMCogUnixBuild|VMUnixBuild]
>> /var/lib/jenkins/jobs/* 
>> 
>> 
>> localdebs: 
>> squeakvm_20131020-1_i386.deb  squeakvm64_20131020-1_i386.deb
> 
> 
>