IDL does HDF 
 
 
Fully supports HDF v. 4.0
Single File Application Interfaces
- access limited to one file at a time
 - supports the 8-bit raster, 24-bit raster, palette, scientific data, and annotation models
 
Multi-File Application Interface
- IDL's interface to HDF's multi-file capability is the HDF_SD_SETEXTFILE routine