Interferometric data files handled by CHAMELEON use the HDS (Hierarchical Data System) format, and have an extension .con for point data files output by CONSTRICTOR and .cha for scan-averaged data output by CHAMELEON. Think of the HDS format as a UNIX directory/file tree contained within a single file. Thus, individual objects can be accessed and modified directly, without having to read through the file until a specific section. The .con files are found in /data/npoi/con on gemini.
Output files produced by CHAMELEON are always stored in the current working directory. Aside from the data file, three types of auxilliary files can be written, files with extension .flg (XDR format) contain the flag tables for interferometric data, .cal (XDR format) contain the calibration table, and .stn (ASCII) contain fitted station coordinates. These files are only written by request, never automatically.
As to auxilliary input files, all these reside in the following directories of the OYSTER home directory. The files used by STARBASE are listed in section 11.4.