Fetching tarball of a commit

[Craig Treleaven]

Hi:

So, I'm back working on a port of MythTV; thanks to Michael Dickens 
for finding and fixing a flaw in the QT4-mac port.  I really want to 
use a recent version of the Fixes/0.25 branch as some bugs affecting 
the Mac were fixed recently.  A Myth dev tells me that GitHub deliver 
the identical zipball for a particular commit (say 9ccfac11f3...) via:

https://github.com/MythTV/mythtv/zipball/9ccfac11f31d8d05d48092efcbec8015c68f6cc1

In Safari, this downloads "MythTV-mythtv-v0.25-84-g9ccfac1.zip".

I've tried several combinations of master_sites, distfiles, and 
distname with little success.  For example ...

set sha1_long       9ccfac11f31d8d05d48092efcbec8015c68f6cc1
master_sites        https://github.com/MythTV/mythtv/zipball/
distfiles           $sha1_long
extract.suffix      {}
checksums           rmd160  08598846aa0cf909a75c67c76183a6d044eff90a \
                     sha256 
e7d681ad0d1e22d87b11779665966627354b71864c4269f1d789cce9649ec120

This fetches a file (named 
"9ccfac11f31d8d05d48092efcbec8015c68f6cc1", 79.5 MB) which passes the 
checksum but fails to unzip, complaining "has more than one 
entry--rest ignored".  I'm still a neophyte with MacPorts, TCL and 
lots of other stuff!  ;)

Any suggestions on how to get this to work?  Might be useful in other 
cases, as well.

Craig