There is only one file type that uses the .TARDIST extension:
TAR Distribution Archive
Archive created for distributing and installing software on Unix-based IRIX systems sold by SGI; often referenced on a webpage and used for installing the software when the link to the file is clicked; similar to the .TAR format and can be opened by some TAR utilities.
TARDIST files are installed by inst, a utility included with IRIX systems. TARDIST files contain scripts that are used by inst for making the software installation. Installed software can be managed using SGI's Software Manager program.
Updated: May 25, 2014