On Thu, Aug 30, 2012 at 9:04 AM, Radostan Riedel
Typically Linux distros don't like duplication of code and don't allow to package something that includes code already packaged. Since mmdb, ssm and libccp4 are used also by coot and other programs, before packaging cctbx it's necessary to hack it so it can be built with external libraries. At least that's my understanding. Thats correct. It is uncomfortable to download software which already distributes other software which they don't develop. Imho this is unnecessary. If everyone would do that we'd have dozens of duplicate libraries.
It is indeed an unfortunate situation, but historically* this was necessary because the license of the CCP4 libraries was ambiguous and/or unacceptable, and we were stuck using an obsolete version for a time. This has been resolved (the libraries are now LGPL, I believe), but Ralf maintained a separate source tree because (among other reasons) he couldn't convince the CCP4 maintainers to accept all of his patches. So the libraries we distribute are not necessarily the same as what you'd be installing system-wide. (I do not actually know what the changes are, but I will ask Ralf.) Note that we also use the ccp4 libraries in SOLVE/RESOLVE, which is part of Phenix, and I suspect that some of the customizations are for that purpose, not CCTBX directly. -Nat (* this predates my involvement, so I apologize if I'm butchering the details)