Routines (alphabetical) > Routines: H > HDF Routines > HDF_SD_START

HDF_SD_START

The HDF_SD_START function opens or creates an HDF file and initializes the SD interface.

Note that every file opened with HDF_SD_START should eventually be closed with a call to HDF_SD_END.

Syntax

Result = HDF_SD_START( Filename [, /READ | , /RDWR] [, /CREATE] )

Return Value

The returned value of this function is the SD ID of the HDF file. If no keywords are present, the file is opened in read-only mode.

Arguments

Filename

A scalar string containing the name of the file to be opened or created. HDF_SD_START can open the following file types: XDR-based NetCDF files, “old-style” DFSD files, or “new-style” SD files. New files are created as “new-style” SD files.

Keywords

READ

Set this keyword to open the SD interface in read-only mode. If no keywords are specified, this is the default behavior.

RDWR

Set this keyword to open the SD interface in read and write mode.

CREATE

Set this keyword to create a new SD file.

Examples

; Open a new HDF file. The file is ready to be accessed:

SDinterface_id = HDF_SD_START('test.hdf', /CREATE)

; When finished with the file, close it with a call to HDF_SD_END:

HDF_SD_END, SDinterface_id

For a more complicated example, see the documentation for HDF_SD_ATTRSET.

Version History

4.0	Introduced