SUMMARY OF RECENT MAJOR CHANGES to LIBG++.
(Also check ../libio/NEWS.)

*** Major changes in libg++ version 2.5:

* The iostream directory is gone.  It has been replaced by ../libio.
The latter is a major re-write.  One major change is that libiostream.a
(which is built in ../libio) can be used indendently of libg++,
which is interesting because you may find its licensing conditions
less onerous.  See ../libio/README.

Also, the guts of the code has been re-written in C instead of C++.
This is so that you can build a C stdio implementation without
a C++ compiler (as was needed before).  However, this is not 100% done.

* There is (preliminary) iostream manual (in ../libio/iostream.texi).

* The files in libg++/g++-include are now obsolete.  Instead, it
is the compiler's responsibility to generate "fixed" copies of your
existing C header files (such as /usr/include/stdio.h).  These copies
(together with a g++ compiler modification) provide C++ access
to the standard C library.  See the fixproto script in the gcc-2.5
distribution.

*** Major changes in libg++ version 2.4:

* The configuration scheme has been largely re-vamped.
Instead of the definitions that are common to all (or many) of
the Makefiles being duplicated in each Makefile.in, they have
now been moved into a shell script libg++/config.shared, which
generates these standard definitions and rules.

Most of libg++/tests/Makefile, which had a lot of regularity,
is now generated by the libg++/tests/Makefile.sh shell script.

Also libg++ no longer uses configure's 'subdirs' mechanism.
Instead, it uses the 'configdirs' mechanism that most Cygnus
packages use.  This means that each directory has its own
configure.in, and each directory can be independently re-configured.

* Lots of fixes have been made so libg++ can be compiled by compilers
other than g++ (specifically cfront), though there are still lots of
warnings.  You may still have to edit some Makefiles etc; this
will probably become easier in the next release.  Many of the
changes involved not depending on g++ extensions.  However, some changes
turned out to be that libg++ was depending on bugs in g++'s overload
resolution.  These bugs in g++ are being fixed; this will cause some
difficulties for libg++.  In some cases, we have decided that the
cleanest fix is removing some libg++ functionality.  Specifically,
the coersions Integer::operator long and Integer::operator double
have been replaced by explicit methods Integer::as_long and
Integer::as_double.  This means you may need to change your code.
Please let us know if this is problematial.

*** Changes in libg++ version 2.3:

* iostream classes use multiple inheritance and virtual base classes.
This is a little more complicated and slightly less efficient,
but saves a slight amount of code duplication.  More importantly,
it improves compatibility with other iostream implementations.

* A few of pseudo-template classes have been converted to use
real templates.  The style used emphasizes sharing code for
multiple template instatiations at the cost of somewhat more
complex internal logic.  No promise is implied about when/if
the remaining ones will be converted.  Using the template classes
assumes gcc-2.3 or similar compiler.

* Added stdiobuf class which provides a streambuf wrapper around
a stdio (FILE*).  This can be useful when mixing C and C++ code.

* streambuf sputn/sgetn virtuals have been made renamed to xsputn/xsgetn,
and sputn/sgetn addedas inline methods.  This change is to be compatible
with AT&T and ANSI; it could require changes to user code if you have
written your own streambuf sub-classes.

* New utils/c++-mode.el (for editing C++ in emacs).

* Lots of little fixes all over.

*** Changes in libg++ version 2.2:

* Accurate input and output of floating-point numbers

* 'make clean' and its variants have been made more consistent.

* Improved portability (SVR4, NeXT, ...)


*** Changes in libg++ version 2.1:

* "Class" include files in g++-include moved to src

Those include files that are just wrappers around C header files
(e.g. signal.h) remain in g++-include, while the header files
that are specific to libg++ (or C++) have been moved to src.
If your system includes "C++-ready" C header files (as in SVR4 or
Linux), you don't need to use the wrappers in g++-include.

* Portability

A lot of effort has gone into making libg++ more portable.
Code that depends on internals of "traditional" implementations
had been made more portable.  The 'libiberty' library is incorporated
into libg++; this supplies (if needed) many functions that may be
missing on particular hosts.

* Auto-configuration

New scripts automaticly figure out various properties of the
system (and compiler) you use.  While these scripts are not
foolproof, the intent is that on most systems you will no longer
have to edit Makefiles or build special configuration files.

* Iostream bug-fixes

There have been numerous bug-fixes and enhancements in the
iostream code.  Lots of rough edges in the streambuf and filebuf
classes have been fixed.

There are still some rough edges of the protocol (as in what the
streambuf class should do, and what sub-classes such as filebuf
should handle).

* iostream enhancements for lexing/parsing.

You can now create a 'streammarker' object, which is a "remembered"
position is a streambuf.  Later, you can backtrack to that position.
This is supposed to work, even if the streambuf is unbuffered and
otherwise unseekable, because the streambuffer never throws away
any data following an extant streammarker.  This feature will be
used to build various scanning/parsing facilities (with backup).
(See iostream.texi for an example.)

* stdio library

Now supports all of ANSI's functionality.

*** Changes in libg++ version 2.0:

* iostream classes

The major change is that input/output uses the new iostream library.
The design is based on (but not identical to) iostreams from
AT&T C++ release 2.x, and the ANSI X3J16/WG21 draft C++ standard.

The iostream classes replace the old stream.  The new
package provides some compatibility hooks.  Including the
obsolete <stream.h> (or defining _STREAM_COMPAT) makes 
more obsolete methods and features available.  However,
you will probably have to change your code if you have used
any libg++-specific extensions (such as the File class).

If you want stick with the old stream classes, change the
definition of IO_DIR in Make.defs (to old-stream).  You will
also need to 'make depend' in directories that contain depend,
and then re-configure everything.  Note that the old-stream
classes are *not* supported and *will* go away in a future release.

* Use g++ version 2 features (if available)

The main one is that an include file g++-include/FOO.h
that is a wrapper for a standard C include file will now
#include_next <FOO.h> instead of #include "/usr/include/FOO.h".
This provides more flexibility wrt to using alternate C libraries
(such as GNU libc), but it is not without its own problems.
For example, if you compile libg++.a with a g++ that has old
incompatible g++-include files in its path, these will be
read (and then in turn read the /usr/include file).  If there
are conflicts, you can remove the previously installed include files,
or try something like 'make XTRAFLAGS=-I/usr/include' (or whatever
include path gcc uses by default).

* Major Makefile changes.
You can now 'make' from any subdirectory.

* Use of 'configure'.

* Copyrights changed to use the Library license version 2.0.
(Some files have not been updated yet; we'll try to finish it for 2.1.)

* The prototype class SplayNode was put into a separate include file
(g++-include/gen/SplayNode.hP).  This is to avoid duplication.
It will require you to generate the approriate SplayNode file
if you use SplayBag, SplaySet, or SplayPQ.

* You can now use inline functions in header files without
having to use either -O or _DUSE_LIBGXX_INLINES.  (The #ifdef
that depended on these has been removed, so inline functions
are inline independent of -O).

* Numerous minor bug-fixes and enhancements.

*** Changes in libg++-1.39.0 from libg++-1.37.0

    * All files use the new g++ #pragma interface / #pragma implementation
      convention, which minimies duplication of `outlined' inlines
      and vtables. This also causes no inlines to be used at
      all when not compiling with `-O', which speeds compilation
      and simplifies debugging.

    * Many .h header file names had to be shortened so as to simulaneously
      work with SYSV and with #pragma interface (since .h and .cc file
      base names must match.) Sorry!

    * All genclass-able files have been moved to g++-include/gen.

    * various and sundry bug fixes, minor enhancements, and/or portability 
        improvements as described in the ChangeLog. 

*** changes from libg++-1.36.3 to libg++-1.37.0

    * Most utility classes and functions are now in stand-alone .cc and/or .h
      files. This should generate smaller exectuables, and, sometimes
      faster compilation. In particular, istream.h, and ostream.h are
      now separately includable. If you only need one, you don't have
      to get the other.

    * The Plex classes now understand `const'. The `changes' and `changed'
      member functions were removed, since it is now possible to
      avoid changes in Plex structures by using const versions.

    * class RandomInteger is available, courtesy of John Reidl.

    * PlotFile3D, a 3D plot class is in libg++/etc. It will be
      incorporated into libg++ proper for the next release, perhaps
       with a few changes. Thanks to Tom Ngo.

    * various and sundry bug fixes, minor enhancements, and/or portability 
        improvements as described in the ChangeLog. 

    * The file etc/HINTS is an emacs RMAIL file that contains recent
        bug-lib-g++ list mail and related messages that may be useful.


*** changes from libg++-1.36.1 to libg++-1.36.3

    * `Tmp' classes have been eliminated from Strings, Integers, etc.
       (Via some retuning of the main classes, Tmp classes were found
        to not significantly impact performance one way or the other,
        so they were removed.)

    * There is now a version of malloc, directly supporting operator
      new, etc. It may be faster and better suited to C++ applications
      than your libc malloc. You should be able to use it unless you need
      a special malloc for a distributed shared memory environment or
      the like. If you can't use it, edit the appropriate flag in
      the top-level Makefile. I would very much appreciate feedback
      about whether this malloc makes any difference in time or space
      efficiency than whatever you are now using.

    * By default, output is now line-buffered. Use the
      NO_LINE_BUFFER_STREAMBUF define in the Makefile to override

    * Otherwise, the stream classes remain C++-1.2 compatible.
      C++-2.0-compatible versions are still in the works.

    * various and sundry bug fixes, minor enhancements, and/or portability 
        improvements as described in the ChangeLog. 

*** changes from libg++-1.35.0 & 1.35.1 to 1.36.1

    * various and sundry bug fixes, minor enhancements, and/or portability 
        improvements as described in the ChangeLog. 

    * Most everything should now work on most SystemV machines. Let me
        know if they don't.

    * genclass now allows an optional prefix to be used instead of type
        name concatenation in order to help minimize filename
        lengths for SYSV users. This is not a great solution, but
        is A solution to filename length problems for SYSV users.

    * Some, but not all classes now behave well with respect to 
      the new 2.0 const specifications. Some uncertainties about
      how g++ will interpret gcc-based const function qualifiers
      (to indicate lack of side effects) versus C++-2.0 const member
      functions has held up the conversion of some classes to use
      const in either or both of these ways.

    * A version of etags suitable for use with c++ is in etc/
        (courtesy of J. Clark)

    * `graph', a unix graph(1) work-alike is in libg++/etc, courtesy
        of Rich Murphey.

    * RAVLMap (Ranked AVLs) prototypes.

    * The GetOpt class & support has been moved from etc/ into libg++.a

    * Streams have been redone to be nearly 100% AT&T 1.2 compatible.
        One minor possible incompatibility exists (ostream<< char)
        that can be eliminated via #define NO_OUTPUT_CHAR at the
        top of stream.h. This is probably necessary in order to
        compile et++. See libg++.texinfo for more details.

        The new stream implementation is not particulary pretty.
        Its main virtue is that it avoids some of the worst things 
        about both AT&T streams and old libg++ streams. A much
        superior AT&T 2.0-iostream superset is in the works
        for future release.

*** changes from libg++-1.25.0 to libg++-1.32.0

    * Nearly all data and methods previously declared as `private'
        are now declared as `protected' to make subclassing from
        library classes easier.

    * Most classes now contain a method `OK()' that checks to
        make sure that an objects internal data is in a valid state.
        See the documentation for further details

    * Mosts tests in ./tests now contain various kinds of assert
        statements. If tests execute without assertion failures,
        and without any other errors that cause aborted execution,
        you may consider them successful. The test files now include
        nearly all of my internal tests, which in turn have been
        made more extensive.

    * Plex classes are available. 
        A bit of propaganda about these:
        Plexes are very attractive replacements for arrays
        in many contexts. Try them!

    * `shrink' and `contains' have been added to Obstack

    * Files and streams have not yet been revamped (a complete
        reworking awaits the AT&T 2.0 stream specification), but
        have been adjusted to provide slightly faster IO in some 
        cases, and now support the use of a user-supplied string 
        to read or write from instead of an actual IO source.

    * Rationals are now normalized when input via `>>'.

    * atoI is fixed.

    * variable-length representations in String, Integer, etc., are
        now completely different. See the documentation for details.

    * New String functions:
       * readline -- read in a line from an istream as a String
       * prepend -- prepend stuff to a String
       * through  -- make a SubString from beginning to match point
       * from     -- make a SubString from match point to end
       * s[i]     -- now returns the char by reference

    * BitVec's are no longer supported, since their capabilities
        are now incorporated in the revised BitString class.

    * stdarg.h and regex.h are revised to support the Sun4

    * Several interesting and/or useful examples of libg++
        class use are in ./etc, mainly courtesy of Doug Schmidt.

    * .cc file names are now all less than 15 characters. Some
        .h file names are longer, but this should not present
        problems on SYSV systems.

    * pseudo-generic `proto' classes have been thoroughly revised:
        * The prototype file names now end in `P', not `.proto'
            and are in the g++-include directory
        * A single, simple-to-use collection traversal mechanism
            via pseudo-indices (`Pix') is used instead of particular
            traversal friend classes.
        * `Bag' prototypes are included
        * Base classes are now supplied, so that all implementations
            of Sets, Bags, are derived, allowing programmers to
            mix and match implementations.
        * They are now simpler to create: all comparison operators
            and the like are now defined as macros in a `defs' file
            which uses some reasonable defaults.
        * The `Dictionary' versions of Set prototypes are not now
            supported. Revised versions of such classes are forthcoming.
        * Class prototypes previously labelled as `Assoc' are now
            called `Maps', with slightly different capabilities.

    * Splay tree prototypes are available.
        A bit more propaganda:  Consider using Splay tree
        based containers (Set, Bag, Map, PQ). They are often
        the most efficient structures when performing mixtures
        of operations (adds, deletes, searches...)

    * Fixed precision reals are available, courtesy of Kurt Baudendistel

    * An ordered hash Set prototype (VOHSet) is available,
        courtesy of Doug Schmidt.

    * MLCG now allows access and modifications to the seeds.

    * The Normal random generator is fixed.

    * SampleStatistic now allows any prob value for confidence
        intervals.

    * some simple timer routines are in builtin.cc, courtesy of Doug Schmidt

    * While the Vec class prototypes are still available, they are
        currently undergoing revision in order to correspond to
        the forthcoming Matrix package (which should be available
        in the next libg++ release).

    * A C++ version of GPERF, a perfect hash function generator
       program is also available in ./etc, courtesy of Doug Schmidt.
 

*** changes from libg++-1.22.2 to libg++-1.25.0

  * All reported errors from the previous release are fixed, and many
    suggested modifications have been performed. Thanks to all who
    have sent bug reports and comments, including those with mail
    addresses that I have not been able to reply to. (My mail connections
    are sometimes more than a little fragile. If you send me mail and
    I have not replied within a few days, you may want to try again. Sorry.)

  * A serious problem in the use of Obstacks by conversion functions 
    has been repaired.

  * A bug in maintaining reference counts on `find' and related operations
    in List prototype classes has been fixed.

  * Strings now support self case manipulation in addition to the
    functional versions.

  * Some new functions have been added to builtin.[h.cc]. All are now
    documented in libg++.texinfo

  * Overload declarations are now performed in std.h and math.h,
    rather than builtin.h,  to eliminate some include file ordering
    problems.

  * Random, RNG, and SampleStatistic classes are available,
    thanks to Dirk Grunwald.

  * A BitVec class is available.

  * The are many new generic container class prototype files. These
    support container classes based on elementary data structures
    (and a couple of non-elementary ones). Please read the documentation.

  * Class prototype OSet has been modified and renamed OLSet.

  * The genclass utility has been modified

*** changes from libg++-1.22.1 to 1.22.2

  * Tests files are now in a separate directory.

  * Several minor errors (Complex unary -, several BitString functions)
    have been repaired.

  * pow(0,0) returns 1 for all versions of pow.

  * An experimental generic class prototyping feature is provided,
    including prototypes for lisp-style lists and ordered list-based sets.

  * several include files with the same names as those in AT&T CC
    are provided. These simply #include other files. OOPS should now
    compile using only g++-include files. See, however, the note
    about struct exception in file math.h

  * Some rearrangement of files containing char* conversion has been
    done to eliminate linking of unnecessary classes.

  * The inline-only-when-optimizing feature is still not supported.

* New Random number generator classes are not yet available. Stubs for
  these files are in this directory. They should be available for next
  release.

*** changes from libg++-1.21.1 to 1.22.0

  * All documentation is in a stand-alone texinfo file, libg++.texinfo,
    and is on its way to becoming a decent piece of documentation.

  * All reported errors from the previous release are fixed, and many
    suggested modifications have been performed. Thanks to all who
    have sent bug reports and comments, including those with mail
    addresses that I have not been able to reply to. (My mail connections
    are sometimes more than a little fragile. If you send me mail and
    I have not replied within a few days, you may want to try again. Sorry.)

  * New Complex, BitSet, and BitString classes are available. You will
    be performing a valuable service if you try these out and report
    back any bugs/comments/suggestions about these or any other classes.

  * File `values.h' has been added. This contains various system
    constants like the number of bits per long, etc. It contains
    much of the same information as sun <values.h>, although a
    few names and things differ slightly.

  * Files `builtin.h', `builtin.cc', and `convert.cc' have been added.
    `builtin' contains common inline and non-inline functions on
    builtin types (like `abs'). `convert' contains code for performing
    IO and char* conversions, mainly via Obstacks. Most of these
    functions are not new -- they have been collected from other .h
    and .cc files.

  * Files `std.h' and `math.h' now declare all libc.a C functions 
    in a way that allows any of them to be overloaded in C++.

  * Strings and Integers now perform expansion via realloc() -- 
    see libconfig.h about whether you should #define SHOULD_FREE_TO_REALLOC.

  * `eatwhite' is supported for istreams.

  * File::getline(String, ...) and get(String) have been removed in order to
    maintain greater independence of different classes.

  * Strings now provide substring matching via new versions of
    `contains' and `matches', `common_prefix' and `common_suffix'.
    Also, there is more support for case operations via `fcompare', etc.
    The versions of `decompose' that do not deal with Regexes have
    been deleted since they provide little functionality over other
    operations. Also, a few special case functions dealing with char*'s
    have been deleted since the required constructors are necessary
    anyway. Several other corrections have been made in String.cc,
    including the elimination of a few aliasing problems.

  * The implementations of Integers and Rationals are now both much
    more efficient and well-tested, while remaining machine independent.
    A few minor visible features have been added and/or changed.
        
  * The `box' command in PlotFile is now simulated, whether or not
    it is present in libplot.a

  * The inlining-only-if-optimizing feature is still not fully implemented.
                 