OGDI has no clear standard for the way to parse the OGDI dataset dictionary and retrieve the list of available layers. And in addition to that, an OGDI client can select only with one layer and family type at any given time. For those reasons, in the current implementation a DataSource can contain only one OGR Layer, corresponding to one OGDI layer and family type.
So the URL used to open a OGDI layer through OGR is the regular GLTP URL to which you append the layer name and family type (separated by colons):
gltp:[//<hostname>]/<driver_name>/<dataset_name>:<layer_name>:<family>Where <layer_name> is the OGDI Layer name, and <family> is one of: "line", "area", "point", or "text".
OGDI coordinate system information is supported for most coordinate systems. A warning will be produced when a layer is opened if the coordinate system cannot be translated.
There is no update or creation support in the OGDI driver.
Raster layers cannot be accessed with this driver but can be accessed using the GDAL OGDI Raster driver.