[Gdal-dev] Opening many HDF subdatasets at once

Frank Warmerdam warmerdam at pobox.com
Thu Feb 8 18:01:34 EST 2007

Peng Gao wrote:
> Is there a limit on the number of HDF subdatasets can be opened at the
> time? I run into a problem where if I open many subdatasets (~10), HDF
> driver fails right way.
> If I open less than many (~10), the 
> driver succeeds first, and but fails later when some opened subdatasets
> are closed,
> and some new ones are opened (the total is less than 10).


The behavior you report sounds like a bug that was fixed sometime between
GDAL 1.3.2 and GDAL 1.4.0 though I don't know the details.  If the problem
exists in 1.4.0 please let me know (via a bug report) and I'll get right on it.

But in any event, the HDF4Image driver does keep at least one handle
on the file open for each instance.  So if you many subdatasets open
at once you will be using up many file handles and there are limits.

Best regards,
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org

More information about the Gdal-dev mailing list