[gdal-dev] How files are handled in OGR / GDAL

Tue Mar 1 12:29:21 EST 2011

Hello List,

I could probably figure it out from the source, but I would apprecaite
if someone could point me in the right direction.

The question is: does GDAL / OGR loads the file in the memory when it
opens in or it just keeps reference to the actual file

Say if I open it, process it etc

hDS =OGROpen  <http://www.gdal.org/ogr/ogr__api_8h.html#123bb02ac8c5cfe143e132f627531125>("point.shp", FALSE, NULL );

....

and then do (without closing)

  poLayer->ResetReading  <http://www.gdal.org/ogr/classOGRLayer.html#ad0f2cd7f0587584b8f382c6a913583c>();

and process again

would it actually trigger re-reading file from the disk or not?

In other words does OGR creates complete memory image for the file or
just reads actual file when it needs something?

Thank you
Mikhail

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