Jeff Whitaker

I have confirmed that this error occurs with both 1.6.1 and current master with hdf5 1.14.0 and netcdf-c 4.9.2.

but the error does not occur with the current master using netcdf-c 4.8.1 and hdf5 1.12.1

a few more data points... (all with latest netcdf4-python master) netcdf-c 4.9.2, hdf5 1.14.0 FAILS netcdf-c 4.9.1, hdf5 1.14.0 FAILS netcdf-c 4.9.0, hdf5 1.12.2 FAILS but netcdf-c 4.8.1, hdf5 1.12.2...

next step will be to create a c example program that triggers the crash and post it to [netcdf-c](https://github.com/Unidata/netcdf-c/issues)

@DennisHeimbigner do you know if there were any changes in netcdf-c 4.9.0 that would have affected creation of compound type elements with lengths greater than 2**16 -1 bytes?

@smndvgnc thanks for doing this! Small point - you don't actually need the `nc_endef` in the C code above (that's only for the old classic format)

filesystem issue?

I can't explain it, but neither can I reproduce it. WIthout that, we don't have much to go on.

Note that 'input/output error' is coming from the OS, and usually indicates a file system issue (such as the disk being full, or a hardware issue).

are you using xarray?