Next: , Previous: Selecting Output File Format, Up: Common features


3.10 Large File Support

Availability: All operators
Short options: none
Long options: none
NCO has Large File Support (LFS), meaning that NCO can write files larger than 2 GB on some 32-bit operating systems with netCDF libraries earlier than version 3.6. If desired, LFS support must be configured when both netCDF and NCO are installed. netCDF versions 3.6 and higher support 64-bit file addresses as part of the netCDF standard. We recommend that users ignore LFS support which is difficult to configure and is implemented in NCO only to support netCDF versions prior to 3.6. This obviates the need for configuring explicit LFS support in applications (such as NCO) which now support 64-bit files directly through the netCDF interface. See Selecting Output File Format for instructions on accessing the different file formats, including 64-bit files, supported by the modern netCDF interface.

If you are still interesting in explicit LFS support for netCDF versions prior to 3.6, know that LFS support depends on a complex, interlocking set of operating system 1 and netCDF suppport issues. The netCDF LFS FAQ at http://my.unidata.ucar.edu/content/software/netcdf/faq-lfs.html describes the various file size limitations imposed by different versions of the netCDF standard. NCO and netCDF automatically attempt to configure LFS at build time.


Footnotes

[1] Linux and AIX are known to support LFS.