[fitsbits] FITS long integer support

On Thu 2004-10-21T10:00:52 -0600, Eric Greisen hath writ:
I did not suggest that we need to avoid files 2 GByte in size, just
constructs like 64-bit integers which are simply not supported on many
computers in any easily accesible way. Thus tables with heaps should
stay 2 GBytes, but we ship 10 GBytes visibility data sets a fair
amount.

But 64-bit integer capability does exist, it is becoming more common,
and it cannot be ignored forever. So again (having been in deep
contact with the culture of the Internet on behalf of the FITS MIME
effort) I find myself echoing the words of the original RFC Editor Jon
Postel from RFCs 791 and 1122 way back at the inception of the
Internet:

Be liberal in what you accept, and conservative in what you send.

Nobody can require that any particular FITS reader evolve to
understand new additions to the standard, but that should not prevent
progress for everyone else. The initial usage of 64-bit capability
will undoubtedly be experimental and only between parties which have
mutual interest and common hardware. But in the case of FITS the
pathway to a 64-bit standard was outlined long ago, and reiterated in
this discussion.

If the FITS community had the financial incentives and backing of the
Internet at large we would already have created the equivalent of an
IETF Working Group, and the outlines that have been given would
already serve as the seeds of a "Proposed Standard" (as seen in
section 4.1.1 of RFC 2026).

I personally expect to be making routine use of 64-bit processors
within the next year. Taking into account the time and effort
required to make a modification of the FITS standard, I assert that it
is already time to begin the process of admitting 64-bit integers to
FITS.

--
Steve Allen UCO/Lick Observatory Santa Cruz, CA 95064
Voice: +1 831 459 3046 http://www.ucolick.org/~sla
PGP: 1024/E46978C5 F6 78 D1 10 62 94 8F 2E 49 89 0E FE 26 B4 14 93