Pnetcdf New File Format

[Katie Antypas]

Hi Rob,

I am testing out the new pnetcdf file format which is supposed to allow 
variable sizes greater than 4GB (as long as they have fewer than 2^31 
elements).  I am running on the Franklin Cray XT4 system at NERSC with 
the PGI compilers and have not successfully created a 1d variable size 
larger than 4GB.  (I'll try multi-dimensions soon.)

I pass "NC_CLOBBER | NC_64BIT_DATA" to ncmpi_create now.  Also, I was 
getting type warnings and noticed a new type int64_t in places where 
type int and MPI_Offset were used before in a number of calls.  What is 
your recommendation to users regarding the int64_t type?  Should they 
replace MPI_Offset with int64_t?

In either case though, if I do or don't make any changes to the ncmpi 
calls (namely ncmpi_create, ncmpi_def_var, ncmpi_put_vara_double_all) 
then I can only create a variable up to 2GB variable size which is under 
2^31 NC_DOUBLE elements in a 1 dimensional array.  (If we were counting 
bytes, rather than doubles my test would be at the 2^31 elements 
limit.)  I didn't think this was the way elements were counted though?

Katie