http://parrot.cs.wisc.edu/externals-private
{endcode}
+Once you place a tarball in =/p/condor/repository/externals= or =/p/condor/repository/externals-private=, you shouldn't change it. You must not change it once a mention of it is pushed to the shared git repository. If the contents of your source tarball(s) may change while you're preparing to push your changes, you have two options for temporarily locating the tarballs:
+
+*: Place the tarball directly in the external's directory and leave the =URLS= file (described below) empty. *Do not push any commits that contain the full tarball to the public git repository.*
+
+*: Place the tarball at some other ftp or http location. Your CS web page or the temporary directory under Condor's anonymous ftp server are possibilities.
+
+In either case, ensure you move the tarball to the official externals location and update the =URLS= file before pushing your changes.
+
{subsection: Making the URLS file}
The =URLS= file is a simple text file containing the URLs of the source tarballs of the external. Normally, there's only one tarball, but a couple externals require several. Each URL should appear on a separate line.
