I have upgraded to GDAL 2.1 on Windows, binaries from: http://www.gisinternals.com/query.html?content=filelist&file=release-1800-gdal-2-1-2-mapserver-7-0-2.zip
I am able to use the command line:
> ogrinfo -al "C:/path/to/my/folder.gdb"
and it works fine, giving me details of the contents.
However, from my C code:
GDALDatasetH dataset = GDALOpen( "C:/path/to/my/folder.gdb", GA_ReadOnly );
I get back NULL, and the console says:
ERROR 4: `C:/path/to/my/folder.gdb' not recognized as a supported file format.
Yet I am still able to successfully open other files with GDALOpen(), such as .tiff, .sid, and others (all rasters, this is the first time I'm trying to open a vector file). Further, when I use GDALGetDriverCount() and GDALGetDriver(), and print the short and long name of each driver, I get a list of 200 drivers, including:
159 ESRI Personal GeoDatabase -- PGeo 160 MySQL -- MySQL 161 ESRI FileGDB -- OpenFileGDB
At one point I was including ogr_FileGDB.dll in my plugins directory, and that was giving a .dll load error on GDALAllRegister() because I don't have the Esri GDB SDK .dlls. But I thought maybe just having ogr_FileGDB.dll in the plugins directory was confusing GDAL and that's why the OpenFileGDB driver wasn't working. But even after removing ogr_FileGDB.dll from the plugins directory, I still get NULL when opening the .gdb.
Any ideas for how I can figure out what's going on?