To use 'hdf format' data file in GrADS

[C. Shaji]

Dear All,
I am using GrADS v1.9b4 on a SunOS 1 5.9 platform. I want to use an 'hdf
format' file in GrADS. I have run GrADS by using gradshdf command.

1) The sdfopen and xdfopen commands give the following error.

ga-> sdfopen month01_combined.hdf
Scanning self-describing file:  month01_combined.hdf
SDF file has no discernable X coordinate.
ga-> xdfopen month01_combined.hdf
Scanning Descriptor File:  month01_combined.hdf
XDFOpen Error:  Unknown keyword in description file
  --> The invalid description file record is:
  --> q?
  The data file was not opened.

2) How can I dump the metadata content into ASCII format (a command
similar to ncdump)?
When I use ncdump, I get the following error.
access1 49% which ncdump
/usr/local/bin/ncdump
access1 50% ncdupm -h month01_combined.hdf | more
ncdupm: Command not found.

3) Is there any way to generate a DDF file and use the hdf file in GrADS?

I would highly appreciate any help in this.

Thanks in advance.

C. Shaji.