Internet Surfer 2.0/Internet Surfer 2.0 (Wayzata Technology) (1996).iso/pc/text/mac/faqs.315

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Frequently Asked Questions (FAQS);faqs.315



@finalout

@titlepage
@title G++ FAQ
@subtitle Frequently asked questions about the Gnu C++ compiler
@sp 1
@author Joe Buck
@page
@end titlepage

@node Top, getting g++, (dir), (dir)
@unnumbered Preface

This is a list of frequently asked questions for g++ users; thanks to
all those who sent suggestions for improvements.

I'm looking for new questions, better answers, or both.  One thing that's
missing is a section on templates and template problems with g++; I'm
looking for contributions on this score.

This FAQ is intended to supplement, not replace, Marshall Cline's
excellent FAQ for comp.lang.c++.  Especially if g++ is the first C++
compiler you've ever used, the question "How do I do <X> with g++?"
is probably really "How do I do <X> in C++?".  You can obtain the
C++ FAQ by anonymous FTP from sun.soe.clarkson.edu [128.153.12.3],
in the file ~ftp/pub/C++/FAQ.  (There is also a mail server for that
FAQ, but it seems to be broken).

@menu
* getting g++::                 Obtaining Source Code
* installation::                Installation Issues and Problems
* User Problems::               User Problems
* legalities::                  What are the rules for shipping code built with g++ and libg++?
@end menu

@node getting g++, installation, Top, Top
@chapter Obtaining Source Code

@menu
* g++ for Unix::                How do I get a copy of g++ for Unix?
* g++ for other platforms::     How do I get a copy of g++ for (some other platform)?
* 1.x vs 2.x versions::         But I can only find g++-1.42!
* latest versions::             What is the latest version of gcc, g++, and libg++?
* should I upgrade?::           I have gcc-2.2.2 and libg++-2.2.  Should I upgrade to the new versions?
@end menu

@node g++ for Unix, g++ for other platforms, getting g++, getting g++
@section How do I get a copy of g++ for Unix?

First, you may already have it if you have gcc for your platform; see
the answer to question 3.

If you're trying to find g++, you can get it by anonymous FTP, by
anonymous UUCP, by buying a tape from the Free Software Foundation,
or by getting it from a friend that has it.

Here is a list of anonymous FTP archive sites for Gnu software.

@example
Japan: ftp.cs.titech.ac.jp, utsun.s.u-tokyo.ac.jp:ftpsync/prep
Australia: archie.au:gnu
Europe: src.doc.ic.ac.uk:gnu, ftp.informatik.tu-muenchen.de,
    ftp.informatik.rwth-aachen.de:pub/gnu,
    nic.funet.fi:pub/gnu, ugle.unit.no, isy.liu.se,
    ftp.stacken.kth.se, sunic.sunet.se, ftp.win.tue.nl,
    ftp.diku.dk, ftp.eunet.ch, archive.eu.net
United States: wuarchive.wustl.edu, ftp.cs.widener.edu,
    uxc.cso.uiuc.edu, col.hp.com, gatekeeper.dec.com:pub/GNU,
    ftp.uu.net:packages/gnu
@end example

The "official site" is prep.ai.mit.edu, but your transfer will probably
go faster if you use one of the above machines.

Users of the HP Precision Architecture (HP-9000/7xx and HP-9000/8xx) may
want to use the "2.3.1-u2" version available from the University of Utah,
site jaguar.cs.utah.edu.  This version supports debugging provided that
gas is used (you need the version of gas available from the same place)
and has several bug fixes that weren't done in time for the 2.3.2
release.  Precompiled binaries of gcc and gdb can also be obtained from
that site.  Hopefully this will all be folded in to 2.4.

UUNET customers can get Gnu sources from UUNET via UUCP.  For information
on how to order tapes from FSF, write to gnu@@prep.ai.mit.edu.

UUCP-only sites can get Gnu sources by "anonymous UUCP" from site
"osu-cis" at Ohio State University.  You pay for the long-distance call
to OSU; the price isn't too bad on weekends at 9600 bps.  Send mail to
uucp@@cis.ohio-state.edu or osu-cis!uucp for more information.

OSU lines are often busy.  If you're in the USA, and are willing to spend
more money, you can get sources via UUCP from UUNET using their 900 number:
1-900-GOT-SRCS (900 numbers don't work internationally).  You will be
billed $0.50/minute by your phone company.

Don't forget to retrieve libg++ as well!

@node g++ for other platforms, 1.x vs 2.x versions, g++ for Unix, getting g++
@section How do I get a copy of g++ for (some other platform)?

The standard gcc/g++ distribution includes VMS support.  Since the
FSF people don't use VMS, it's likely to be somewhat less solid than
the Unix version.  Precompiled copies of G++ and libg++ in VMS-installable
form are available by FTP from mango.rsmas.miami.edu.

DJ Delorie has ported gcc/g++ to MS-DOS; this port is popularly known as
"DJGPP" (the P's stand for "plus").  It can be found on many FTP archive
sites; its "home" is on grape.ecs.clarkson.edu, directory
~ftp/pub/msdos/djgpp.  Make sure you're retrieving the current version,
which should indicate that it is a port of gcc-2.2.2 (2.3.1 and 2.3.2 have
been released since then, but I don't think the DOS port is done yet).  It
is also available on site wuarchive.wustl.edu, in directory
mirrors/msdos/djgpp, and many other places as well.

For information on Amiga ports of gcc/g++, retrieve the file
/pub/gnu/MicrosPorts/Amiga from prep.ai.mit.edu, or write
to Leonard Norrgard <vinsci@@nic.funet.fi>, who I hope won't be too upset
that I mentioned his name here.

A port of gcc-2.3.1 to the Atari ST can be found on the site
``atari.archive.umich.edu'', under /atari/Gnustuff/Tos, along with many
other Gnu programs.  See the FAQ for the Usenet group
``comp.sys.atari.st'' for more information.

There are two different ports of gcc-2.2.2 (and g++) to OS/2, the
so-called EMX port, which requires a particular Unix emulator, and
a port called ``gcc/2'', which runs native.  The latter port uses
a rather buggy port of the BSD libc.  For more information ask
around on comp.os.os2.programmer.  gcc/2 can be obtained by FTP
from

@example
ftp-os2.nmsu.edu (128.123.35.151) in /pub/os2/2.0/programming/gcc2-222
luga.latrobe.edu.au (131.172.2.2) in /pub/os2/2.0/programming/gcc2-222
@end example

Eberhard Mattes did the EMX port.  Tevor Lampre did the gcc/2 port.
Their addresses are mattes@@azu.informatik.uni-stuttgart.de and
mmtl@@cc.flinders.edu.au, repectively.

Because the legal policies of Apple threaten the long-term goals of FSF,
as well as the concept of free software, no support will be lent to
efforts to port Gnu software to Macintosh or other Apple hardware.

@node 1.x vs 2.x versions, latest versions, g++ for other platforms, getting g++
@section But I can only find g++-1.42!

``I keep hearing people talking about g++ 2.3.2 (or some other number
starting with 2), but the latest version I can find is g++ 1.42.
Where is it?''

As of gcc 2.0, C, C++, and Objective-C as well are all combined into a
single distribution called gcc.  If you get gcc you already have g++.  The
standard installation procedure for any gcc version 2 compiler will
install the C++ compiler as well.

One could argue that we shouldn't even refer to "g++-2.x.y" but it's a
convention.  It means "the C++ compiler included with gcc-2.x.y".

@menu
* latest versions::             What is the latest version of gcc, g++, and libg++?
@end menu

@node latest versions, should I upgrade?, 1.x vs 2.x versions, getting g++
@section What is the latest version of gcc, g++, and libg++?

The latest "2.x" version of gcc/g++ is 2.3.2, released Nov 27, 1992.
The latest version of libg++ is 2.3, released Dec 9, 1992.

For some non-Unix platforms, 2.2.2 may be the latest compiler that
has been ported.  libg++ 2.3 will not compile with gcc-2.2.2.  Also,
due to a newly introduced compiler bug, libg++ 2.2 will not compile
with gcc-2.3.1 or gcc-2.3.2.

The latest "1.x" version of gcc is 1.42, and the latest "1.x" version of
g++ is 1.42.0.

@node should I upgrade?,  , latest versions, getting g++
@section I have gcc-2.2.2 and libg++-2.2.  Should I upgrade to the new versions?

Unfortunately, this question cannot be answered with a simple yes or no.
gcc-2.3.x made some significant improvements in template support;
however, at the same time, quite a few new bugs were introduced in
2.3.1, particularly in resolving of overloaded functions.  2.3.2 fixed
some of them, but serious problems remain (for example, 2.3.2 cannot
compile some perfectly correct code in libg++-2.2).  Given this, I would
recommend that those not using templates wait for a more stable release
(gcc-2.3.3 should be out soon).  If you're using templates and 2.2.2
won't cut it for you, by all means upgrade.

@node installation, User Problems, getting g++, Top
@chapter Installation Issues and Problems

@menu
* gcc-2 + g++-1::               I can't build g++ 1.x.y with gcc-2.x.y!
* what else do I need?::        OK, I've obtained gcc; what else do I need?
* use Gnu linker?::             Should I use the Gnu linker, or should I use "collect"?
* Use Gnu assembler?::          Should I use the Gnu assembler, or my vendor's assembler?
* Use Gnu C library?::          Should I use the Gnu C library?
* Problems building libg++ on Ultrix::  Problems building libg++ on Ultrix
@end menu

@node gcc-2 + g++-1, what else do I need?, installation, installation
@section I can't build g++ 1.x.y with gcc-2.x.y!

``I obtained gcc-2.x.y and g++ 1.x.y and I'm trying to build it, but
I'm having major problems.  What's going on?''

If you wish to build g++-1.42, you must obtain gcc-1.42 first.  The
installation instructions for g++ version 1 leave a lot to be desired,
unfortunately, and I would recommend that, unless you have a special
reason for needing the 1.x compiler, that C++ users use g++-2.3.2, as it
is the version that is being actively maintained.

There is no template support in g++-1.x, and it is generally much further
away from the ANSI draft standard than g++-2.x is.

@node what else do I need?, use Gnu linker?, gcc-2 + g++-1, installation
@section OK, I've obtained gcc; what else do I need?

First off, you'll want libg++ as you can do almost nothing without it
(unless you replace it with some other class library).

Second, depending on your platform, you may need "gas", the Gnu assembler,
or the Gnu linker (see next question).

@node use Gnu linker?, Use Gnu assembler?, what else do I need?, installation
@section Should I use the Gnu linker, or should I use "collect"?

First off, for novices: special measures must be taken with C++ to arrange
for the calling of constructors for global or static objects before the
execution of your program, and for the calling of destructors at the end.
(Exception: System VR3 and System VR4 linkers support user-defined
segments; g++ on these systems requires neither the Gnu linker nor
collect.  So if you have such a system, the answer is that you don't
need either one).

If you have experience with AT&T's "cfront", this function is performed
there by programs named "patch" or "munch".  With Gnu C++, it is performed
either by the Gnu linker or by a program known as "collect".  The collect
program is part of the gcc-2.x distribution; you can obtain the Gnu linker
separately as part of the "binutils" package.

(To be technical, it's "collect2"; there were originally several
alternative versions of collect, and this is the one that survived).

There are advantages and disadvantages to either choice.

Advantages of the Gnu linker:

It's faster than using collect -- collect basically runs the standard Unix
linker on your program twice, inserting some extra code after the first
pass to call the constructors.  This is a sizable time penalty for large
programs.  The Gnu linker does not require this extra pass.

Gnu ld reports undefined symbols using their true names, not the mangled
names.

If there are undefined symbols, Gnu ld reports which object file(s) refer to
the undefined symbol(s).

Advantages of collect:

If your native linker supports shared libraries, you can use shared
libraries with collect.  The Gnu linker does not (yet) support shared
libraries.

The Gnu linker has not been ported to as many platforms as g++ has, so you
may be forced to use collect.

If you use collect, you don't need to get something extra and figure out
how to install it; the standard gcc installation procedure will do it for you.

In conclusion, I don't see a clear win for either alternative at this
point.  Take your pick.

@node Use Gnu assembler?, Use Gnu C library?, use Gnu linker?, installation
@section Should I use the Gnu assembler, or my vendor's assembler?

This depends on your platform and your decision about the Gnu linker.  For
most platforms, you'll need to use gas if you use the Gnu linker.  For
some platforms, you have no choice; check the gcc installation notes to
see whether you must use gas.  But you can usually use the vendor's
assembler if you don't use the Gnu linker.

The Gnu assembler assembles faster than many native assemblers; however,
on many platforms it cannot support the local debugging format.

@node Use Gnu C library?, Problems building libg++ on Ultrix, Use Gnu assembler?, installation
@section Should I use the Gnu C library?

At this point in time, no.  The Gnu C library is still very young, and
libg++ still conflicts with it in some places.  Use your native C library
unless you know a lot about the gory details of libg++ and gnu-libc.  This
will probably change in the future.

@node Problems building libg++ on Ultrix,  , Use Gnu C library?, installation
@section Problems building libg++ on Ultrix

``I am having trouble building libg++-2.2 on Ultrix [and possibly other
systems].  I get errors referring to "dummy.o".  Help!''

(The errors on Ultrix end with something like

@example
ldopen: cannot open dummy.o
nm: Error: cannot open dummy.o
ldopen: cannot open dummy.o
nm: Error: cannot open dummy.o
nm failed to find FUNC in dummy.o!
sh: -1: bad number
*** Error code 1
@end example

@noindent
and there may be similar problems on other systems).

The fix for this is to make libg++ by saying "make CC=gcc".

@node User Problems, legalities, installation, Top
@chapter User Problems

@menu
* static data members::         Linker reports undefined symbols for static data members
* placement new syntax::        g++ won't accept the placement new syntax.
* bug reports::                 I think I have found a bug in g++.
* porting to g++::              Porting programs from other compilers to g++
* name mangling::               Why does g++ mangle names differently from other C++ compilers?
* problems linking with other libraries::  Why can't g++ code link with code from other C++ compilers?
* documentation::               What documentation exists for g++ 2.x?
* agreement with standards::    What are the differences between g++ and the ARM specification of C++?
* compiling standard libraries::  Will g++ compile InterViews?  The NIH class library?
* debugging on SVR4 systems::   Debugging on SVR4 systems
@end menu

@node static data members, placement new syntax, User Problems, User Problems
@section Linker reports undefined symbols for static data members

``g++ reports undefined symbols for all my static data members when I link,
even though the program works correctly for compiler XYZ.  What's going on?''

The problem is almost certainly that you don't give definitions for
your static data members.  If you have

@example
class Foo @{
    ...
    void method();
    static int bar;
@};
@end example

you have only declared that there is an int named Foo::bar and a member
function named Foo::method that is defined somewhere.  You still need to
defined BOTH method() and bar in some source file.  According to the draft
ANSI standard, you must supply an initializer, such as

@example
int Foo::bar = 0;
@end example

@noindent
in one (and only one) source file.

@node placement new syntax, bug reports, static data members, User Problems
@section g++ won't accept the placement new syntax.

``I have a program that uses the "placement syntax" of operator new,
e.g.

@example
   new (somewhere) T;
@end example

@noindent
and g++ won't accept it.''

Up until version 2.3.1, g++ accepted an alternate form of the placement
syntax, for historical reasons; use

@example
   new @{somewhere@} T;
@end example

@noindent
if you are using g++-2.2.2 or older.

As of 2.3.1, g++ finally fixed this, using the standard ARM syntax for
"placement new".  A few remaining glitches were fixed in 2.3.2.  The
only remaining problem is with declarators for pointers to functions;

@example
new (void (*)(int));  // confuses gcc 2.3.2
new (a) (void (*)(int)); // ditto
@end example

These can be worked around with a typedef:

@example
typedef void (*fun)(int);
new fun;
new (a) fun;
@end example

@node bug reports, porting to g++, placement new syntax, User Problems
@section I think I have found a bug in g++.

``I think I have found a bug in g++, but I'm not sure.  How do I know,
and who should I tell?''

First, see the excellent section on bugs and bug reports in the gcc manual
(which is included in the gcc distribution).  As a short summary of that
section: if the compiler gets a fatal signal, for any input, it's a bug.
Same thing for producing invalid assembly code.

I will add some extra notes that are C++-specific, since the notes from
gcc are generally C-specific.

First, mail your bug report to "bug-g++@@prep.ai.mit.edu".  You may also
post to gnu.bug.g++, but it's better to use mail, particularly if you
any doubt as to whether your news software generates correct reply
addresses.  Don't mail C++ bugs to bug-gcc@@prep.ai.mit.edu.

If your bug involves libg++ rather than the compiler, mail to
bug-libg++@@prep.ai.mit.edu.  If you're not sure, you could send your bug
to both lists.

Second, if your program does one thing, and you think it should do
something else, it is best to consult a good reference if in doubt.  The
standard reference is "The Annotated C++ Reference Manual", by Ellis and
Stroustrup (copyright 1990, ISBN #0-201-51459-1); the reference manual,
without annotations, also appears in Stroustrup's "The C++ Programming
Language, Second Edition" (copyright 1991, ISBN #0-201-53992-6).  Both are
published by Addison-Wesley.

Note that the behavior of (any version of) AT&T's "cfront" compiler is
NOT the standard for the language.

@node porting to g++, name mangling, bug reports, User Problems
@section Porting programs from other compilers to g++

``I have a program that runs on <some other C++ compiler>, and I want
to get it running under g++.  Is there anything I should watch out
for?''

First, see the questions on placement new syntax and static data members.

There are two other reasons why a program that worked under one compiler
might fail under another: your program may depend on the order of
evaluation of side effects in an expression, or it may depend on the
lifetime of a temporary (you may be assuming that a temporary object
"lives" longer than the standard guarantees).  As an example of the
first:

    void func(int,int);

    int i = 3;
    func(i++,i++);

Novice programmers think that the increments will be evaluated in strict
left-to-right order.  Neither C nor C++ guarantees this; the second
increment might happen first, for example.  func might get 3,4, or it
might get 4,3.

The second problem often happens with classes like the libg++ String
class.  Let's say I have

String func1();
void func2(const char*);

and I say

    func2(func1());

because I know that class String has an "operator const char*".  So what
really happens is

    func2(func1().convert());

where I'm pretending I have a convert() method that is the same as the
cast.  This is unsafe, because the temporary String object may be deleted
after its last use (the call to the conversion function), leaving the
pointer pointing to garbage, so by the time func2 is called, it gets an
invalid argument.

If you think this is ugly, you should know that the ANSI C++ committee is
STILL debating the lifetime-of-temporaries problem.

For now, the safe way to write such code is to give the temporary a name,
which forces it to live until the end of the scope of the name. For
example:

    String& tmp = func1();
    func2(tmp);

Finally, like all compilers (but especially C++ compilers, it seems),
g++ has bugs, and you may have tweaked one.

@node name mangling, problems linking with other libraries, porting to g++, User Problems
@section Why does g++ mangle names differently from other C++ compilers?

See the answer to the next question.

@node problems linking with other libraries, documentation, name mangling, User Problems
@section Why can't g++ code link with code from other C++ compilers?

``Why can't I link g++-compiled programs against libraries compiled by
some other C++ compiler?''

Some people think that, if only the FSF and Cygnus folks would stop being
stubborn and mangle names the same way that, say, cfront does, then any
g++-compiled program would link successfully against any cfront-compiled
library and vice versa.  Name mangling is the least of the problems.
Compilers differ as to how objects are laid out, how multiple inheritance
is implemented, how virtual function calls are handled, and so on, so if
the name mangling were made the same, your programs would link against
libraries provided from other compilers but then crash when run.  For this
reason, the ARM *encourages* compiler writers to make their name mangling
different from that of other compilers for the same platform.
Incompatible libraries are then detected at link time, rather than at run
time.

@node documentation, agreement with standards, problems linking with other libraries, User Problems
@section What documentation exists for g++ 2.x?

Almost none.  The gcc manual describes the C front end, and also the back
end, which is shared by the C++ compiler, but there is almost no
documentation for the C++ front end.  There is a Unix-style manual entry,
"g++.1", in the gcc-2.x distribution; this describes the extra
command-line options that g++ supports, and the #pragma interface and
#pragma implementation directives.

A draft of a document describing the g++ internals appears in the 2.3.2
distribution (called g++int.texi); it is still incomplete.

Work is proceeding on a user g++ document; with luck it will appear in the
next release.

@node agreement with standards, compiling standard libraries, documentation, User Problems
@section What are the differences between g++ and the ARM specification of C++?

The chief thing missing from g++ that is in the ARM is exceptions (the
other major compilers do not have exceptions either).  There are bits
and pieces of exception code present, but it is not presently usable.

While, as of 2.3.1, the "placement new" syntax finally agrees with the
ARM, there are still some problems with it.

The template implementation is still new.  The implementation in 2.3.2
represents a considerable improvement over that of previous releases,
however.  Still, it has many bugs.

g++ does not implement a separate pass to instantiate template functions
and classes at this point; for this reason, it will not work, for the most
part, to declare your template functions in one file and define them in
another.  The compiler will need to see the entire definition of the
function, and will generate a static copy of the function in each file
in which it is used.

As with any beta-test compiler, there are bugs.  You can help improve
the compiler by submitting detailed bug reports.

[A full bug list would be very long indeed, so I won't put one here.
I may add a list of frequently-reported bugs and "non-bugs" like the
static class members issue mentioned above].

@node compiling standard libraries, debugging on SVR4 systems, agreement with standards, User Problems
@section Will g++ compile InterViews?  The NIH class library?

The NIH class library uses a non-portable, compiler-dependent hack
to initialize itself, which makes life difficult for g++ users.
It will not work without modification, and I don't know what modifications
are required or whether anyone has done them successfully.

Brendan Kehoe of Cygnus is working on getting NIHCL to build with g++.
He says, "The NIHCL release will hopefully contain patches to gcc 2.3 to
let it build."

[ From Stienar Bang <steinarb@@idt.unit.no> ]

The C++ compiler part of gcc-2.3 (when released) *should* be able to
compile InterViews release 3.1 (when released) out of the box (no
patches required on either side).

[ Now that 2.3.1 is out, is this true? ]

@node debugging on SVR4 systems,  , compiling standard libraries, User Problems
@section Debugging on SVR4 systems

``When I use the -g flag on C++ code on a System V Release 4 system,
I get lots of undefined symbols at link time.  Why?  Help!''

[From Ron Guilmette:]
The changes needed to get the g++ front-end to generate proper DWARF style
debugging information for System V Release 4 are not yet completed, nor
will they be until g++ version 2.4 (at the earliest).

There is nothing that you (as an end-user) can do to correct this problem.
(It is actually *many* problems, and they are all very complex.)  Until
the g++ maintainers have time to fix this, you should simply *avoid* using
the -g option when using g++ on SVR4.

@node legalities,  , User Problems, Top
@chapter What are the rules for shipping code built with g++ and libg++?

``Is it is possible to distribute programs for profit that are created
with g++ and use the g++ libraries?''

I am not a lawyer, and this is not legal advice.  In any case, I have
little interest in telling people how to violate the spirit of the
Gnu licenses without violating the letter.  This section tells you
how to comply with the intention of the Gnu licenses as best I understand
them.

The FSF has no objection to your making money.  Its only interest is that
source code to their programs, and libraries, and to modified versions of
their programs and libraries, is always available.

The short answer is that you do not need to release the source to
your program, but you can't just ship a stripped executable either.

Compiling your code with a Gnu compiler does not affect its copyright;
it is still yours.  However, in order to ship code that links in a Gnu
library such as libg++ there are certain rules you must follow.  The
rules are described in the file COPYING.LIB that accompanies gcc
distributions; it is also included in the libg++ distribution.
See that file for the exact rules.  The agreement is called the
Library Gnu Public License or LGPL.  It is much "looser" than the
Gnu Public License, or GPL, that covers must Gnu programs.

Here's the deal: let's say that you use some version of libg++,
completely unchanged, in your software, and you want to ship only
a binary form of your code.  You can do this, but there are several
special requirements.  If you want to use libg++ but ship only object
code for your code, you have to ship source for libg++ (or ensure
somehow that your customer already has the source for the exact
version you are using), and ship your application in linkable form.
You cannot forbid your customer from reverse-engineering or extending
your program by exploiting its linkable form.

Furthermore, if you modify libg++ itself, you must provide source
for your modifications (making a derived class does not count as
modifying the library -- that is "a work that uses the library").

@page
@contents
@bye
--
Joe Buck    [e-mail]
Xref: bloom-picayune.mit.edu comp.graphics:34039 news.answers:4741
Path: bloom-picayune.mit.edu!enterpoop.mit.edu!hri.com!spool.mu.edu!sdd.hp.com!elroy.jpl.nasa.gov!ufo!grieggs
From: [e-mail] (John T. Grieggs)
Newsgroups: comp.graphics,news.answers
Subject: (21Dec92) comp.graphics Frequently Asked Questions (FAQ)
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Date: 21 Dec 92 17:02:30 GMT
Expires: Mon, 4 Jan 1993 17:02:30 GMT
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This message is automatically posted once a week or so in an effort to
cut down on the repetitive junk in comp.graphics.  It was last changed
on 21Dec92.  If you have answers to other frequently asked questions that
you would like included in this posting, please send me mail.  If you
don't want to see this posting every week, please add the subject line
to your kill file.  Thank you.