Reviewing this patch, it seems like a reasonable thing to allow a Tcl installation to be configured for a site in a standard way. In particular, allowing control over the places to search for packages without having to change init.tcl seems fair (and reasonable for apps that aren't using a *kit build). However, I'm not sure if the location selected by this patch is the best that could be chosen, and I'm not sure whether any per-user locations should be supported. This change should be considered to be an RFE that requires a TIP.