[MacPorts] #17477: Integrate *_select tools into port

[MacPorts]

#17477: Integrate *_select tools into port
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 Reporter:  blb@…             |       Owner:  macports-tickets@…                   
     Type:  enhancement       |      Status:  new                                  
 Priority:  Normal            |   Milestone:  MacPorts 1.8.0                       
Component:  base              |     Version:  1.7.0                                
 Keywords:  select            |        Port:                                       
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Comment(by perry@…):

 For the sake of completeness (mostly as a proof of concept), I've quickly
 implemented --show in r44056.  It needs to be written ASAP (for reasons
 that will be obvious when you look at the code ;)).

 The main problem is that the currently selected version is not logged when
 using a *_select tool (and of course port select).  Using the current
 method I've implemented won't work if (1) more than one version symlinks
 to the same file or (2) there are no symlinks (e.g., 'none' for the
 'python' group).

 We should standardize how the currently selected version for each group is
 logged.  One thought is have a symlink in the confpath that points to the
 currently selected version.  As an example:

 {{{
 perry at phoenix /opt/local/etc/select/python $ ls -l
 total 20
 -rw-r--r-- 2 root admin 310 2008-12-16 20:34 base
 -rw-r--r-- 2 root admin  24 2008-12-16 20:34 none
 -rw-r--r-- 2 root admin 344 2008-12-06 18:35 python25
 -rw-r--r-- 2 root admin 151 2008-12-16 20:34 python25-apple
 lrwxr-xr-x 1 root admin   8 2008-12-19 23:24 selected -> python25
 }}}

-- 
Ticket URL: <http://trac.macports.org/ticket/17477#comment:8>
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