What is needed is a foolproof way of saying "I want this, please send it to me" and then being able to reject it safly without needing the other party to do it for you.
This can be done today if you are able to create email addresses on the fly. This is supported
by several mailing systems (Qmail or Postfix, for example):
Create a new email address. Include a secret key in it if you want to be sure that
is cannot be easily guessed. In case of Qmail:
If you want to unsubscribe and you encounter difficulties to do this directly,
just let all messages bounce to the specific email address you have created. In case of Qmail:
If he were on the SPEWS's blocklist, he'd never get out!
And this is why the SPEWS blocklist is so effective and so good.
The problem with SPEWS is the refusal to consider appeals.
Out of their FAQ:
Q16: I'm not a spammer or spam operation... heck I hate spam, but my email is getting bounced by
someone using SPEWS, or I can't access a website due to SPEWS based blocking.
A16: You maybe part of the rare "inadvertent blocking" that can occur when a spam friendly provider is listed in spews. Your best option is to try and educate your provider or switch
to one who is not listed in SPEWS as spam friendly. SPEWS aims to avoid listing any non-spammer or
non-spam support areas if possible - we just want to stop spam.
[...]
Q41: How does one contact SPEWS?
A41: One does not. SPEWS does not receive email - it's just an automated system and website, general blocklist related issues can be discussed in the public forums mentioned above.
Every blocklist has sooner or later false positives. When there is no way to handle complaints then this list is more harmful than good.
I don't see why anyone should mourn the passing of proprietary hardware,[...]
The SPARC processor is covered by IEEE Standard 1754-1994 and licensed by the non-profit organization SPARC International Inc.. You can, for example, buy SPARC-compliant hardware from Fujitsu and run Solaris on it.
Object is functionally equivalent to void *, with a little runtime type checking added.
It is not just a question about type checking but also of being able to restore correctly the original type in case of a heterogenous list. In C++, dynamic_cast does not work if the given type does not include virtual methods.
Your program still crashes if you misuse it,
This assumption is not correct. A misuse of void *, i.e. a wrong cast does not automatically crash your program. Unfortunately one of the greatest problems with C and C++
is that many problems of this kind are initially survived which, under some circumstances, might
open interesting security holes.
I just disagree with the claim that C++ *forces* you to use templates for generic programming by not providing alternatives.
Well, I do not consider alternatives that cause me to lose type safety. void * was introduced in C to get rid of char * as a generic pointer type in the context of storage management. It is the correct type of malloc(). Fortunately, we have a new operator in C++ and do not need void * any longer except for some low-level tricks.
If I wanted to cast to void *, I'd be casting to void *; I am not prevented from doing this in C++. Java just enforces it, albiet via a lack of templates.
This is simply nonsense. Java does not enforce it. It is even not allowed in Java because Java has a safe type system unlike C++. There exist no such thing like a void * in Java nor is it possible to cast something to it. The base class Object is something completely different in Java as you do not lose type safety using it.
But ((void *) 0) is no longer the same as 0. This difference could be critical if you assign it to a pointer. Please note that C++ compilers are free to chose another representation than all-bit-zero for pointers. If you assign an explicit 0 to a pointer, it can be treated correctly by the compiler. This, however, is no longer true if you play games with casts. That it still works on many platforms does not mean that it is correct.
Now you know why generics are being added to Java.
This was not a discussion whether we want to use templates or not but about how expensive they are. Templates cause more code to be generated for several instances of lists than Java where we have just one piece of code handling all lists. That the lists of Java do not allow you to restrict a particular instance to bananas is nothing new. Nor is the discussion about OO techniques vs templates / generics something new. That discussion was already started long ago with the paper ``Genericity vs Inheritance'', SIGPLAN Notices, vol 21, no 11, November 1986, by Bertrand Meyer.
I can cast to (void *) in C++ just as well as I can in Java.
Sure, you can do this. But do you really want to leave the type system even for a list of bananas or apples? One important reason (among many others) to use templates in C++ is to survive the absence of a general base class without giving up type safety.
Please get rid of NULL completely, not just in the context of a string initialization. NULL is a relict of ancient C times and it might even hit you in C++ if NULL is not 0. This is thoroughly explained in 5.1.1 in Stroustrup's book about C++.
That's object files, not code. Code is what a developer writes. If a developer doesn't write it, it's not code; it's a build product.
That is your private terminology but not that of the field. The final phase of a compiler is called code generation and the result is code. Yes, code has multiple meanings and this is just one of them. For this reason, compiler writers (like me) prefer to speak about source text for the input of a compiler to distinguish it from the code which is the preferred term for the output of a compiler.
Using the STL and templates, you will tend to have less code, not more.
Not necessarily. Just consider the alternatives to templates and forget for a little moment about being enforced to templates in C++ because of a missing general base class (like Object in Java). If you have templates, you will get duplicated code for each different template instantiation. Code duplication, however, does not happen if you write some general code that works for some base class. Take List in Java, for example. You have the code of List just once even if you have several lists, one with apples and the other with bananas.
You'll probally want to get a book or other such better documentation.
If you want to do serious work with the STL, it might be a good idea to take the original ISO 14882-1998 standard for C++ which is available for US$ 18. Many of the fine points are unfortunately missing or simply plain wrong in the manual pages of various C++ STL vendors and/or in various STL books.
I'm looking forward to somebody starting over some day and coming up with a language that supports generic programming as well as C++, but which doesn't have the terrible syntax of C++ templates. It must be possible.
Do you have considered Eiffel or Ada? Both come with generic programmic and with a far more friendly syntax. However, they require you to specify type constraints. This adds security, it makes clear what the requirements of a type you want to pass as template argument are. But it is also more restrictive than C++.
In general, most oddities of C++ including its syntax are simply due to the heritage of C. And if a large framework is given, there are not so many options left to add something like templates. As in the case for member functions, you have to repeat the whole prefix over and over again because there is no construct that encloses the members outside the class declaration. They can be even spread over as many source files as you like. And <...> most likely was introduced for template parameters instead of (...) to avoid ambiguities. The result seems to be a fair deal. After all, the use of a template does not look that bad. Just the templates themselves look like a mess.
I am member of a club which is a fully fledged ISP including its own independent IP address space, high bandwidth, backup connections, enough room for co-located servers, and even commercial customers which help to finance our toys. We do not just offer dial-in via modems or ISDN but also plan to provide DSL (not an easy task in Germany). Interesting projects like voice over IP are also supported.
All this works thanks to volunteers. They payoff is that we have a great freedom and services that are not to be found everywhere like static IP addresses (if necessary, in connection with CIPE tunnels), incredibly cheap co-location, and the option of sharing. What's more, we meet each other every week in our own cellar and enjoy some beer:-)
OpenBSD claims to be ultra-secure because Theo has personally read every line of code, but in truth it's really sort of amateurish and its "amazing" history of few exploits is due to the fact that its userbase is like five people, including Theo's dead mother and his dog Farmer, whom he has hot dog sex with.
Remove one of them. Apparently, Dan Bernstein
switches from OpenBSD to FreeBSD. He observed, as can be seen on his
cr.yp.to mainpage, a large number of OpenBSD crashes including following:
2002.02.26 ~17:30 GMT through ~19:30 GMT:
OpenBSD network stack crash.
The load was not heavy (about 20 web downloads per second from slashdot,
plus a few mail deliveries per second)
and presumably would have been handled without trouble
by the FreeBSD network stack.
Please consider that this ``handheld'' has dimensions of 5.4" x 4" x 1.1" and a weight of 20oz (567g). This is neither something like a palmtop (except for very large palms) nor one of these slim notebooks. While it is without question quite some achievement to squeeze all this stuff into this format, you might still wonder if it is practical.
You cannot (or better: you shouldn't) publicly mirror a web page without the consent of its author.
I guess that the forewarning of slashdotted web site owners is usually sacrified toward more actual news. But even then the web site owner should be able to create mirrors himself and to ask for an update of the corresponding/. entry.
Ah... this reminds me to my first notebook in 1991: a Dell 320N with a 386 (20Mhz), a 60MB disk, and 5MB memory. 10MB were dedicated to a minimal DOS partition. The rest (including 10MB swap) was used for Interactive UNIX as Linux wasn't an option at that time. You could run X windows on it, using the tiny uwm (universal window manager). troff and a previewer were included as well which allowed me to type my PhD thesis on it. The nice point
was that you could run all these tools without needing even swap space.
Unfortunately, that notebook died in 1995 and it was too expensive to repair it (Dell asked for DM 600).
PGP was free from the start, just
check out the
license of PGP 2.6.3. But even if it starts free, copyright holders can turn their package into a non-free status in later releases.
I guess my real question was, what's so good about the SPARC.
Admitted -- new boxes are fairly expensive for private use. Until now Sun has a price policy that gives significant savings only for educational institutions and companies that spend huge sums for Sun hardware.
But it is no problem to get used Sun hardware for low prices. Maybe they are not the machines of your choice on your desktop but they are great network servers and the pizza box cases consume less space in 19" racks than standard PC hardware. Except for the newer Ultras, Sun hardware is well manufactured and runs (in most cases) without trouble for years.
why is it so rare to actually find people using one?
Well, I guess you'll find some of them in this thread:-)
You do not need frame buffers, mice, keyboards
and monitors to take advantage of a little
SPARC box. Just put it into your network and
use a console at installation time (a notebook
with a serial cable will do it).
I got myself four SPARCstation-4s for free
from a company
who no longer needed them. They came
without memory or disks but these parts were
easily bought.
Now, two of them reside in 19" racks at some
providers and need only 2 units each. Try to
beat this with PCs that usually take 4 units.
I asked CRC Press for some background of this
case and they pointed me to
this court document which concludes with the
order
to shut down mathworld.wolfram.com.
Slashdot Mirror
This can be done today if you are able to create email addresses on the fly. This is supported by several mailing systems (Qmail or Postfix, for example):
maildirmake ~/mailbox/cryptogram
echo './mailbox/cryptogram/' >~/.qmail-cryptogram1234567'
echo | QMAILSUSER=cryptogram1234567 qmail-inject \
crypto-gram-subscribe@chaparraltree.com
echo '|bouncesaying "Good bye!"' \
>~/.qmail-cryptogram1234567
And this is why the SPEWS blocklist is so effective and so good.
The problem with SPEWS is the refusal to consider appeals. Out of their FAQ:
Every blocklist has sooner or later false positives. When there is no way to handle complaints then this list is more harmful than good.
The SPARC processor is covered by IEEE Standard 1754-1994 and licensed by the non-profit organization SPARC International Inc.. You can, for example, buy SPARC-compliant hardware from Fujitsu and run Solaris on it.
It is not just a question about type checking but also of being able to restore correctly the original type in case of a heterogenous list. In C++, dynamic_cast does not work if the given type does not include virtual methods.
This assumption is not correct. A misuse of void *, i.e. a wrong cast does not automatically crash your program. Unfortunately one of the greatest problems with C and C++ is that many problems of this kind are initially survived which, under some circumstances, might open interesting security holes.
Well, I do not consider alternatives that cause me to lose type safety. void * was introduced in C to get rid of char * as a generic pointer type in the context of storage management. It is the correct type of malloc(). Fortunately, we have a new operator in C++ and do not need void * any longer except for some low-level tricks.
This is simply nonsense. Java does not enforce it. It is even not allowed in Java because Java has a safe type system unlike C++. There exist no such thing like a void * in Java nor is it possible to cast something to it. The base class Object is something completely different in Java as you do not lose type safety using it.
But ((void *) 0) is no longer the same as 0. This difference could be critical if you assign it to a pointer. Please note that C++ compilers are free to chose another representation than all-bit-zero for pointers. If you assign an explicit 0 to a pointer, it can be treated correctly by the compiler. This, however, is no longer true if you play games with casts. That it still works on many platforms does not mean that it is correct.
This was not a discussion whether we want to use templates or not but about how expensive they are. Templates cause more code to be generated for several instances of lists than Java where we have just one piece of code handling all lists. That the lists of Java do not allow you to restrict a particular instance to bananas is nothing new. Nor is the discussion about OO techniques vs templates / generics something new. That discussion was already started long ago with the paper ``Genericity vs Inheritance'', SIGPLAN Notices, vol 21, no 11, November 1986, by Bertrand Meyer.
Sure, you can do this. But do you really want to leave the type system even for a list of bananas or apples? One important reason (among many others) to use templates in C++ is to survive the absence of a general base class without giving up type safety.
Please get rid of NULL completely, not just in the context of a string initialization. NULL is a relict of ancient C times and it might even hit you in C++ if NULL is not 0. This is thoroughly explained in 5.1.1 in Stroustrup's book about C++.
That is your private terminology but not that of the field. The final phase of a compiler is called code generation and the result is code. Yes, code has multiple meanings and this is just one of them. For this reason, compiler writers (like me) prefer to speak about source text for the input of a compiler to distinguish it from the code which is the preferred term for the output of a compiler.
And if you don't believe me, look it up in the Jargon:
Not necessarily. Just consider the alternatives to templates and forget for a little moment about being enforced to templates in C++ because of a missing general base class (like Object in Java). If you have templates, you will get duplicated code for each different template instantiation. Code duplication, however, does not happen if you write some general code that works for some base class. Take List in Java, for example. You have the code of List just once even if you have several lists, one with apples and the other with bananas.
If you want to do serious work with the STL, it might be a good idea to take the original ISO 14882-1998 standard for C++ which is available for US$ 18. Many of the fine points are unfortunately missing or simply plain wrong in the manual pages of various C++ STL vendors and/or in various STL books.
Do you have considered Eiffel or Ada? Both come with generic programmic and with a far more friendly syntax. However, they require you to specify type constraints. This adds security, it makes clear what the requirements of a type you want to pass as template argument are. But it is also more restrictive than C++.
In general, most oddities of C++ including its syntax are simply due to the heritage of C. And if a large framework is given, there are not so many options left to add something like templates. As in the case for member functions, you have to repeat the whole prefix over and over again because there is no construct that encloses the members outside the class declaration. They can be even spread over as many source files as you like. And <...> most likely was introduced for template parameters instead of (...) to avoid ambiguities. The result seems to be a fair deal. After all, the use of a template does not look that bad. Just the templates themselves look like a mess.
I am member of a club which is a fully fledged ISP including its own independent IP address space, high bandwidth, backup connections, enough room for co-located servers, and even commercial customers which help to finance our toys. We do not just offer dial-in via modems or ISDN but also plan to provide DSL (not an easy task in Germany). Interesting projects like voice over IP are also supported. All this works thanks to volunteers. They payoff is that we have a great freedom and services that are not to be found everywhere like static IP addresses (if necessary, in connection with CIPE tunnels), incredibly cheap co-location, and the option of sharing. What's more, we meet each other every week in our own cellar and enjoy some beer :-)
Remove one of them. Apparently, Dan Bernstein switches from OpenBSD to FreeBSD. He observed, as can be seen on his cr.yp.to mainpage, a large number of OpenBSD crashes including following:
Looks like as if OpenBSD was /.-ed.
Some background materials:
Honestly, this stuff is already bad enough. Hard to imagine how nuclear weapons can be considered again.
They still contaminate the site they have hit, though.
This wasn't challenged yet to my knowledge. But it is at least disputed.
Please consider that this ``handheld'' has dimensions of 5.4" x 4" x 1.1" and a weight of 20oz (567g). This is neither something like a palmtop (except for very large palms) nor one of these slim notebooks. While it is without question quite some achievement to squeeze all this stuff into this format, you might still wonder if it is practical.
You cannot (or better: you shouldn't) publicly mirror a web page without the consent of its author. I guess that the forewarning of slashdotted web site owners is usually sacrified toward more actual news. But even then the web site owner should be able to create mirrors himself and to ask for an update of the corresponding /. entry.
Unfortunately, that notebook died in 1995 and it was too expensive to repair it (Dell asked for DM 600).
PGP was free from the start, just check out the license of PGP 2.6.3. But even if it starts free, copyright holders can turn their package into a non-free status in later releases.
Admitted -- new boxes are fairly expensive for private use. Until now Sun has a price policy that gives significant savings only for educational institutions and companies that spend huge sums for Sun hardware.
But it is no problem to get used Sun hardware for low prices. Maybe they are not the machines of your choice on your desktop but they are great network servers and the pizza box cases consume less space in 19" racks than standard PC hardware. Except for the newer Ultras, Sun hardware is well manufactured and runs (in most cases) without trouble for years.
why is it so rare to actually find people using one?
Well, I guess you'll find some of them in this thread :-)
I got myself four SPARCstation-4s for free from a company who no longer needed them. They came without memory or disks but these parts were easily bought.
Now, two of them reside in 19" racks at some providers and need only 2 units each. Try to beat this with PCs that usually take 4 units.
I asked CRC Press for some background of this case and they pointed me to this court document which concludes with the order to shut down mathworld.wolfram.com.