Many of you running the protected mode MS-DOS binary have noticed that
certain operations are unacceptably slow.  This is a result of the
data librarian feature, where all the data files for help,
monster/object info, special levels, etc. are lumped into one file
(NHDAT).

I posted a message previously about a non-DLB binary I made
available, but there's another option.  I've uploaded the DLB utility
(which unfortunately was not included in the offical distribution) to
win.tue.nl and it is now in .../Msdos/Utils/dlb320pm.zip.  Using this
utility, you can pull the data files out of NHDAT to make those slow
operations faster.

PLEASE NOTE that this utility is only for the protected mode version.
I haven't tried it with the real mode version.  I'm not sure it would
work, and I'm not sure you'd need it anyway.  I've never tried the
real mode version so I don't know if it suffers the same slowdown as
the protected mode version.

There are two ways of handling this.  The first (easier, and my
preferred solution) is to simply go to your game directory and execute
"dlb x" followed by "dlb c nul" to extract all of the data files into
the current directory and leave a dummy NHDAT (the nethack binary
requires this file to be present, even if it isn't used for anything).

The second option, if you don't want to clutter your game directory
with all of those .LEV files, requires a bit more work.  You can
extract only those files which are used most often.  You should at
least extract the file called "data".  You may have to experiment to
see which files are used often enough to annoy you if left in NHDAT.
Here is the procedure:

1. Create and go to an empty directory and copy DLB.EXE and NHDAT to
that directory.

2. Execute "dlb t > dlb.lst"

3. Edit dlb.lst and delete the line containing "Directory" (should be
the first line) and also the lines containing names of files you want
to extract (i.e. "data" and any others you want to pull out).

4. Execute "dlb x".  This extracts all of the data files into the
current directory.  Move the files whose names you deleted from
dlb.lst (i.e. "data" and any others) to your game directory.

5. Execute "dlb cI dlb.lst" to build a new NHDAT containing the
left over files.

6. Move the new NHDAT to your game directory.

7. Delete all the files from the current directory and remove the
directory.

This feature may seem a little roundabout, but unfortunately the DLB
utility provides no easy way to delete files from NHDAT.

If you have any problems or discover any mistakes in this procedure,
send me mail at jgt2@Lehigh.EDU.