[comp.lang.fortran] Cray to Sun unformatted data file conversion

mckie@amelia.nas.nasa.gov (William McKie) (02/19/90)

Does anyone know of a program which converts a Cray unicos fortran
unformatted variable length record file to a logically equivalent
file readable on a Sun-4 with Sun fortran?

The Cray file records consist of 64 bit REAL and INTEGER words only,
and it is desired that the Sun file contain 32 bit REAL and INTEGER
words (ieee).  Cray REALs with magnitude not representable in the
32 bit Sun format could be set to extreme values, or to one of the
ieee special values.  Cray INTEGERs with magnitude not representable
in the 32 bit Sun format could be truncated to the low order 32 bits.
It would be nice to run the translation program on the Cray side, and
then transfer the Sun image file over a network to the Sun.

Is this doable without the program knowing record lengths and the
structure of INTEGERs and REALs within each Cray record?  Can Cray
REAL words be distinguished in all cases from Cray INTEGER words?
Can the Sun fortran binary file structure be constructed on the
Cray side without interference from Cray internal blocking control
words?  [I think the Sun fortran unformatted variable length record
structure has a 32 bit integer record size byte count preceding and
following each record's data bytes.) 

Thanks,
Bill McKie
NASA Ames Research Center
mckie@sky.arc.nasa.gov