HDFGETANN Function
Obtains HDF object (e.g., an SDS, Raster 8 image, etc.) annotations, either a label or a description.
 
Restriction
See "Supported Platforms Guide" on the PV-WAVE Documentation website to check if this function is available on your operating system.
Usage
status = HDFGETANN (filename, tag, ref)
Input Parameters
filename—The name of the HDF file.
tag—The HDF tag number associated with the annotation.
ref—The HDF reference number of the target object.
Return Value
status—The status of the function call, where:
*SUCCEED (0)—Indicates success.
*FAIL (–1)—Indicates failure.
Keywords
Description—A byte array that contains the description for the specified filename/tag/ref object. This byte array may require further processing for display of the description.
Help—If present and nonzero, lists the usage for this routine.
Label—A string variable that contains the label for the specified filename/tag/ref object.
Usage—If present and nonzero, lists the usage for this routine. (Same as the Help keyword.)
Discussion
HDFGETANN is used to get a label or description for an arbitrary HDF object, as specified by a filename/tag/ref triplet.
Example
hdf_init
@hdf_common
testfile = !Data_dir + '/raster8.hdf'
tag = DFTAG_RI8
ref = 2
newdesc = BYTE (' ')
status = HDFGETANN (testfile, tag, ref, Description=newdesc)
IF (status EQ FAIL) THEN $
   MESSAGE, 'Failed HDFGETANN with Description.' $
ELSE PRINT, STRING (newdesc)
See Also
Also refer to the following routines in the HDF Reference Manual:
DFANGETDESC, DFANGETDESCLEN, DFANGETLABLEN, DFANGETLABEL, DFANPUTDESC, DFANPUTLAB
For more information on using the HDF interface and the calling sequence for the entire suite of HDF base functions, refer to Appendix A: PV-WAVE HDF Interface.
For a complete list of the HDF convenience routines, refer to Chapter 1: Functional Summary of Routines.