install multiple versions of a library

[Ryan Schmidt]

On Dec 30, 2012, at 11:16, Federico Beffa <beffa at ieee.org> wrote:

> after some month I updated my ports and find that the newer version of the program "xsane" has a bug and does not close properly (segmentation fault. The bug has already been reported).
> 
> Now I could in principle revert to the previous version. However, the older version does not run because during the update the library libpng has been updated from version 1.4 to 1.5 and the older version of xsane has been compiled against 1.4. Therefore I would have to revert to libpng14. This would in turn break all programs compiled during the update against libpng15.
> 
> My question is: is there a clean way to have both library versions installed at the same time?

Not really.

You could try downgrading xsane to the older working version, and rebuilding it against libpng 1.5.

https://trac.macports.org/wiki/howto/InstallingOlderPort