For bugs fixed in the current release see RELEASE.txt file
For bugs fixed in all releases after HDF4.2r0-Beta see HISTORY.txt file.

HDF4.2r0-Beta
========
1. "hdp dumpgr" and "hdp dumpsds" have two new options:
        -g to suppress the data of global (or file) attributes
        -l to suppress the data of local attributes

2. The problem where hdp failed on very long file name has been
   fixed. (bug #693)

3. The problem where VSinquire failed when being called on a vdata
   that has no fields defined, has been fixed. (bug #626)

4. A user attempted to change the values of VGNAMELENMAX and VSNAMELENMAX
   to 256 for her own use, but the hdp output showed that the change was
   not in effect.  This problem is now fixed. (bug #606)

5. hdp dumpvg failed sometimes when reading a file that has a vgroup 
   being inserted into another.  This has been fixed. (bug #477)

6. fp2hdf when used with -p option did the opposite of what it was supposed
   to do with palette files. This problem is now fixed. (bug #800). However
   the utility hdfimport should be used in the future instead of fp2hdf.

7. hdf2gif failed when a user tried it on JPEG compressed images. (Bug #601).
   The problem is now fixed. An error message is displayed if the image is not
   8-bit. If the image is 24-bit, the message suggests using hdf2jpeg.

8. ncdump failed to read NetCDF files 3.5 when there were more than one variable
   with unlimited dimensions. Fixed.

9. NetCDF part of the HDF4 Library was not ported to Compaq True64 system. Fixed.

10. The hdp commands dumpsds, dumpgr, dumpvd, and dumpvg now display an 
    informative message when a non-HDF file is given as input. (Bug #817)

11. The compilation warnings and error on the macro HDFclose are fixed.
    (Bug #818)

HDF4.1r5
========
1. The following VS routines are added as requested (bug #267):
     VSsetblocksize/vsfsetblsz -- sets the block size of the linked-block element.
     VSsetnumblocks/vsfsetnmbl -- sets the number of blocks for 
                                  a linked-block element.
     VSgetblockinfo/vsfgetblinfo -- retrieves the block size and the 
                                    number of blocks of a linked-block element.

2. When using SDsetdimscale to set the data type for a dimension to 
   an unsigned type, the type became signed inadvertently (bug #172).  
   This problem is now fixed.

3. The memory leak in the netCDF part of the HDF/mfhdf distribution
   is fixed. (bug #418)

4. When using "hdp dumpgr", data was being printed in the range of 0-250
   when it should be 0-168 (bug #422).  This problem is now fixed.

5. hdp dumpgr has a new option to print palette data only -pd.  Also,
   whenever option -p or -pd is given, only palettes are printed, no 
   images nor file attributes. (bug #439)

6. The "#define NULL" was removed since ANSI C compilers are required to
   define NULL. (bug #448)

7. Giving NULL to the fieldname argument in VSsetfields now returns
   FAIL instead of causing segmentation fault. (bug #554)

8. Giving a NULL to the argument name in several name setting routines
   now returns FAIL instead of causing segmentation fault. (bug #514)

9. Two routines were added to get compression information for the SD and
   GR interfaces, including chunked elements: SDgetcompress/sfgcompress 
   and GRgetcompress/mggcompress. (bug #307)  
   Note: 
   - for a JPEG image, GRgetcompress only returns the compression type, not 
     the compression information (i.e, quantity and force_baseline) because 
     this information currently is not retrievable.
   - getting compression type for JPEG chunked images is not working yet.

10.  Added new fortran function heprntf (HEprint) that takes two
     arguments: file name and level. If file name string has 0 length
     error messages will be printed to the standard output. 

11.  Fix the linking bug of unresolved symbol(error_top) DLL when HEclear 
     was called by users. Users who want to use hdf DLL should define HDFAPDLL 
     in their applications. Simply going to project setting and adding HDFAPDLL
     as the predefined constant should work.

HDF4.1r4
========
1. Fixed GR JPEG compression problem.
2. Added -s, -c and -l options to hdp.

HDF4.1r3
=========
1. HDF 4.1r2 was unable to properly read HDF SDSs created with HDF 3.3x.
   It did not read the correct SDS names.  This problem has been fixed.
2. Many problems with the GR interface were fixed:
   - The GR interface can now read compressed files created with the
     DFR8 and DF24 interfaces, except for those which were compressed
     with IMCOMP compression.
   - The GR interface can read and write images compressed with RLE,
     GZIP and Skipping Huffman compression methods.
   - Palettes can now be written and read properly with the GR interface.
   - 24-bit raster images can now be read by the GR interface.
3. You can now create an SDS with a name up to 256 characters in length.
   The previous limit was 64.
4. SDfileinfo no longer returns the wrong number of datasets for old
   files created with the DFSD interface.
5. The Vdata/Vgroup interfaces in HDF did not check return values, which
   caused problems on the Macintosh, and could have potentially caused
   problems on all platforms.  HDF now checks all return values properly.
6. Several missing Fortran functions have been added to the
  ./include/dffunc.inc file.
7. Calling SDreaddata after setting the fill value and before doing
   an SDendaccess and SDend caused a core dump on IRIX6.x with the
   -64 bit option.  This problem has been fixed.
8. Many hdp fixes were made:
   - Options 'o' and 'b' or 'x': it used to be that you had to give -o
     in order for -b or -x to be valid; now you can just give -b or -x
     and the output will go to the screen.  Basically, you can have either
     binary or ASCII text to the screen now where it used to be just ASCII.
   - Options (-r,-i,-n,-c) can be given on the same command line; previously
     the last option overrode all the previous ones.
   - Added printing of GR file attributes (bug #192)
   - Added printing of a palette to the dumpgr command (bug #252) with the new
     option -p
       -p : print palette info and data
       -p -h : print palette info
       -p -d : print palette data
   - Added printing of SD file attributes to the dumpsds command
   - The -c option for dumpvd used to only show the first vdata; now all vdatas
     of the same class show for option -c.  Also, multiple class names listed
     with this option are searched; they used to be ignored.
   - Added printing file annotations to the dumpvd command.
   - Improved output wording for the dumpvd command.  For example, <Undefine>
     gets printed instead of nothing, or FULL_INTERLACE/NO_INTERLACE is printed
     instead of "0/1".
   - In one case the dumpvg command would get into an infinite loop.  This
     problem has been fixed.
   - With the dumpvg command, all vgroups of the same class show for option -c;
     previously only the first one was shown.  Also, multiple class names listed
     with this option are now searched; they used to be ignored.
   - File annotations can now be printed with the dumpvg command.
   - With the dumpvg command, occasionally a core dump occurred when printing
     the Graphical Representation part if multiple hdf files were given.  This
     has been fixed.

HDF4.1r2
========
1. The hdp utility can now dump data properly to a binary file (using
   the -b option).
2. HDF no longer core dumps when reading a NetCDF file.
3. HDF now supports little-endian conversion for VAX and Dec Alpha OpenVMS.
4. The SD interface can now properly handle writing to a one-dimensional
   array that is unlimited.
5. The SD interface can now properly handle attributes with a data type
   of Little Endian.
6. HDF will no longer fail if you write data to a vdata that had no data 
   written to it when it was first created.
7. The problems that occurred on the Crays with HDF 4.1r1 have been
   corrected.

HDF4.1r1
========
1. A bug was fixed where you would receive an error if you changed the 
   name of a Vdata to a name that was longer than the original name.
2. The FORTRAN equivalents have been added for several ANxx utility routines 
   (ANget_tagref, ANid2tagref ...).
3. A bug was fixed where old data (DFSD) in native and little endian format 
   could not be read by the SD interface correctly.
4. The variable _HDF_ENTIRE_VDATA has been changed to _HDF_VDATA, to avoid 
   confusion.  This variable had been added to HDF 4.1b1.  For those
   users who are already using it, a macro called  _HDF_ENTIRE_VDATA has been
   added, which is defined as _HDF_VDATA.
5. SD_FILL and SD_NOFILL were added as file fillmodes.   
6. In HDF 4.0r2, you could create an empty compressed SDS.  With 4.1b1 you
   could not.  This was fixed in the 4.1 release. 
7. There was a bug in hdp where 'hdp list -a' did not list the file attributes. 
   This was fixed.
8. In 4.1b1, the SD chunking routine names contained upper case characters
   after the initial two "SD" characters (for eg. SDwriteChunk).  With 4.1r1
   the SD chunking routine names were changed to lower case after the
   initial "SD" characters, to be consistent with the SD interface 
   naming scheme (for eg. SDwritechunk). 

HDF4.1b1
========
1. If you opened a file in read only mode with the SD interface,
   it would create the file if the file did not exist. This has been fixed.
2. There was a problem with GRstart, which caused GRend to
   trigger a segmentation fault when it was called twice.
   This has been fixed.
3. DFNT_UCHAR has been added to hdf_unmap_type.  
4. A problem was fixed in HDc2fstr, which caused garbage to
   be attached to a converted string.
5. The multi-file annotation functions were added to dffunc.inc.
6. A bug was fixed in the DFPnpals function, where it would return
   the wrong number of palettes.
7. A problem was fixed with the gzip compression, where an error
   occurred if you attempted to write to an SDS that you have created, and 
   then performed an SDendaccess, followed by a SDselect.
8. HDF4.0r2 did not recognize JPEG images created by HDF 3.3r4.  This
   has been fixed.
9. The newest SGI cc compiler (7.0) has eliminated the compression code
   errors when '-O' option is used.

HDF4.0r2
========
1. SDstart (<non-existent file>, DFACC_RDWR) no longer fails.
   It will create a file now.
2. When appending compressed data onto the end of an unlimited
   dimension SDS, the SD interface no longer writes the fill-
   values in locations where they will immediately be over-
   written by data.
3. dfkcray.c, IEG2JPEG and JPEG2IEG do not work if the foreign
   data does not start from the 64-bit boundary.
4. On IRIX 6.1 with -n32,  hdf/test/comp.c gave error messages.
   Fix: Not to use '-O' option (for now).
5. Problem when running 'make test' on UNICOS has been fixed
   (bug was in hdf/util/he_main.c).
6. The RIG tag was not getting written out when creating a
   GR object, so you couldn't view it with "hdp list". The hdp
   command has been updated.

HDF4.0r1p1
==========
1. Fixed a bug in SDS interface which caused a wrong
   number of records for UNLIMITED dimensions when 
   ncsync was called to write data to hdf files. 
2. A bug has been fixed in the UNLIMITED dimension record 
   to improve backward compatibility.
3. Parameter 'class' in vffndcls() has been changed to 
   'vgclass' to avoid conflicts with C++ reserved word 
   'class'.

HDF4.0r1
========
1. Fixed Fortran character string handling under UNICOS. 
2. Added checks on the return values of HDmalloc calls. 
3. The automatic test of hdf utilities (in hdf/util/) 
   is added to the Makefile and will be executed by 
   'make test' at the top level. 
4. Thanks to Mark W. Dalton for his contribution to the fix
   of the adaptive Huffman compression on the CRAY YMP. 
   His fix is merged into 4.0r1.
5. Added check in SDsetattr() to make sure that the argument 
   'count' < MAX_ORDER.

HDF4.0b2
========
1. To avoid conflicts with C++, field name 'new' in vgroup_desc 
   of vg.h is changed to 'new_vg', and in accrec_t 'new' of 
   hfile.h is changed to 'new_elem'.
2. Fixed the max number of fields of vdata in vparse.c, vshow.c 
   and show.c (in mfhdf/dumper/). Now vshow and hdp can dump
   VSFIELDMAX number of fields. 
3. Fixed platform number subclass problem when external data file was
   written in Little_endian format (IBM-PC). 
4. Fixed the core-dump on some machines when writing large number of 
   big SDS by holding the buffer instead of freeing it every time.
5. The max number of files which can be open at one time was defined
   in hdf.h, hfile.h and netcdf.h. Now there is only one definition
   by MAX_FILE in hdf/src/hlimits.h.
6. A bug in SDsetnbitdataset is fixed. 
7. Uninitialized memory reads in SDIputattr and hdf_create_dim_vdata
    are fixed. 

HDF4.0b1
========
1. Added support to unsigned integers for attributes.
2. Bug fixed in SDsetdimscale if dim strings or other attributes already
   assigned to that dimension and if the size of the number type
   is not 4 bytes. 
3. Bug fixed in SDgetdimscale.  For dimensions that have no dim scale 
   SDgetdimscale now returns 0 for nt to indicate that  no-scale was assigned.
4. Several buffers allocated by Hxxxx, SDxxxx, and VSxxxx functions were 
   used through the entire excecution time of HDF application programs.
   In previous releases those buffers were not freed by HDF. Some debugging 
   tools list those buffers as memory leaks. In HDF4.0b1 those buffers are freed
   by HDF when the programs exit. The fix doesn't work on SunOS.  
5. Added Fortran version of VSQueryxxxx and VSfind:
     vsqfnelt -- VSQuerycount
     vsqfintr -- VSQueryinterlace
     vsqfflds -- VSQueryfields
     vsqfvsiz -- VSQuerysize
     vsqfname -- VSQueryname
     vsffnd   -- VSfind
6.  SDsetdimscale () did not set scales for unlimited dimension. 
    After appending records to the unlimited dimension, the number of 
    records was not updated.  The bug is fixed. 
7.  In previous releases, the Vdata interface couldn't define more than 36 
    fields even though VSFIELDMAX was defined as 64 in hdf.h. 
    The bug is fixed. Now the maximum number of fields is decided by
    VSFIELDMAX. 
8.  The Fortran function sfgdinfo now returns nattr correctly.
9.  hdfrseq is moved out from the HDF release. It is now available on the NCSA
    ftp server in directory: /HDF/contrib/NCSA/hdfrseq/.
10. If the same file is accessed twice with DFSDputdata (i.e. the file 
    is first destroyed), the first call to DFANputlabel after the second 
    call to DFSDputdata fails. To fix this problem, a new function 
    DFANclear has been added. 
    -----------------------------------------------------------------
    Name:    DFANclear
    Purpose: Clear DFAN interface
    Inputs:  void
    Returns: SUCCEED if ok; FAIL otherwise.
    Remarks: When a file is re-created in a single run, user should
             call DFANclear() before the file is re-created to reset DFAN 
             interface structures.
    Example: 
             main()
             {
                  int ret;
                  dump(0);  /* DFSDputdata("myfile.hdf",...) is called  */
                            /* in dump() to create myfile.hdf  */
                  ret = DFANclear();
                  dump(1);  /* DFSDputdata("myfile.hdf",...) is called  */
                            /* again to re-create a file with the same  */
                            /* name myfile.hdf  */
             }

11. A bug is fixed in SDgetcal, which failed in getting number_type from 
    old hdf files, created by DFSDxxxx calls.  
12. hdf.inc missing constants and commas
13. HDgettagname() can't recognize DFTAG_FV and DFTAG_COMPRESSED
    in hkit.c  
14. fp2hdf is back in hdf/util/.

--------------------------------------------------------------

Known problems:
1. Need Fortran version of VFfieldxxxx functions.
2. Need an easy way to append to a vdata. One solution would be 
   to make all FULL_INTERLACE vdatas appendable.
3. Need a high level function to create external Vdata, similar to 
   SDsetexternalfile(). 
4. SDxxxx interface creates dummy values for dimension records. 
   For multi-dimensional SDS this isn't too bad. However, for 
   1-D SDS it doubles the size of the file. 
