Truncation Output Issue: Fileset Flag and Filename Handling

[ezhilsabareesh8]

In the current version of MOM6 with FMS2, truncation outputs are not produced when the fileset flag is set to SINGLE_FILE. This PR address issue 736 by setting the MULTIPLE and fixing the file handle check in MOM_PointAccel.F90.

Note that this is a temporary fix to produce the truncation output by setting the fileset toMULTIPLE. The patches can be removed when the official fix is updated in MOM6.

[aekiss]

LGTM, thanks @ezhilsabareesh8. Any reason to have a 50 char limit for filename? Bytes are cheap :-)

[ezhilsabareesh8]

Thanks @aekiss In the original code, an uninitialized value was being passed to open() for the filename, which was misinterpreted as a massive string. This caused the following error when fileset was set to MULTIPLE:

forrtl: severe (66): output statement overflows record, unit -5, file Internal Formatted Write

I resolved the issue by switching to a fixed-length filename, which eliminated the error. I set the limit to 50 characters, though there's no specific reason for choosing this length. Increasing it to 200 or more might be safer, but GFDL typically prefers to avoid fixed-length filenames if possible. For the official fix, I hope they will develop a flexible solution that avoids this limitation.

[ezhilsabareesh8]

I have increased the char limit for filename, tested it and it is producing truncation output.