[fitswcs] coordinates by table lookup

[Mark Calabretta]

On Mon 2002/10/28 11:53:40 CDT, William Pence wrote
in a message to: Mark Calabretta <Mark.Calabretta at atnf.CSIRO.AU>
and copied to: fitswcs at NRAO.EDU

>Files on tape are not supported by this convention.  Even if there were a
>way to refer to tape files, it would not be very useful within this context
>if the tape is offline and there is no way for the software to automatically
>access it. 

Let me put it another way.  Suppose I have a collection of these files
sitting on a disk and I want to archive them to tape (DLT say).  What
happens to the file references?  Do I have to use a tape backup program
which preserves the directory structure, e.g. tar (unix) or BACKUP (VMS)?
Will this be portable?  (The "T" in FITS.)

Then what happens to URLs like '/local/user/wcsfile.fits' or
'ftp://nrao.edu/pub/wcsfile.fits' when I unload the tape elsewhere?

Or maybe I have to merge the files into one FITS file when the tape is
written?

Cheers, Mark