Vortex: how?

#pragma comment( linker, "/ENTRY:_entrance@0" ) 
void _stdcall entrance( void ) {
    return;
}

//or

#pragma comment( linker, "/ENTRY:entrance" ) 
void _cdecl entrance( void ) {
    return;
}
    

#pragma comment( linker, "/MERGE:.text=.data" )
#pragma comment( linker, "/MERGE:.rdata=.data" )
#pragma comment( linker, "/SECTION:.flat,RWE" ) //new section RWE access
#pragma comment( linker, "/MERGE:.data=.flat" )
    

fox wrote:

I think they compile to machine language.. but you are better away from them. Delphi is the OOP version of Pascal, and it was mainly supported by Borland. But Borland has abandonned it..

That's not true. A simple console hello world I made here is 9 216 bytes. I also speed tested Delphi against gcc some time ago, and it produces faster code.

The exes are only big if you use the predefined library of GUI components. This is the same for any language. An hello world compiled with gcc: 509 576 bytes

Code:

#include <cstdlib>
#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    system("PAUSE");
    return EXIT_SUCCESS;
}    

And I don't think it's abandoned, they just released Delphi 2006.

cout << "Hello, world!\n";
    

f0dder, I'm sure some of that functionality is in the OS, so the size comparison probably ain't entirely fair.

Besides, there are better examples (see below) than this useless snippet we're referring to.

Also, I wonder why it links in the whole printf() if the string requires nothing but a puts().

UPX 2.00 for DOS (DJGPP2/COFF): 647,168 bytes (277,676 packed)
UPX 2.00 for Windows (WIN32/PE): 490,496 bytes (198,144 packed)

P.S. OpenWatcom 1.5 is released (only Win32 and OS/2 install packages, for now).

Because I used `printf` and not `puts` ^_^ - on purpose, to show that you can get printf without very much overhead.

For DOS, you need a *lot* of code because there's not much OS support.

If you look at the UPX source you'll see that it is *not* a very pretty sight

That's interesting - I haven't used Watcom for several years. How is it's code generation compared to VC7 and later? It used to be good in the DOS days, but last I checked Intel and Microsoft compilers produced quite better results.

I don't have VC7 or Intel compilers, so I dunno.

OW has been called the potential DJGPP killer (if you can believe that!).

P.S. I know this is the wrong thread, but...UPX has no memory overhead for most formats.

I'm not too fond of DJGPP, although it was my main C++ compilers years back. Has to do with it's file format and the standard library. If I needed to do 32bit dos development these days, I would use Visual C++ and probably the HX dos extender.

The Visual C++ Toolkit 2003 has been replaced by Visual C++ 2005 Express Edition. Visual C++ 2005 Express Edition provides a complete integrated development and debugging environment making it the easiest way to create powerful applications using the C/C++ language. Visual C++ 2005 Express Edition also contains an enhanced version of the C/C++ optimizing compiler for the fastest executables. Best of all, the Visual C++ 2005 Express Edition is completely free!

BTW, your VC link at http://f0dder.has.it is outdated.

I was thinking about downloading the express edition, since it's now forever free... but it seems it requires winxp sp2, and mine is sp1

It might be possible to manually extract the install files and get just the compiler, linker and libraries that way... haven't tried, though.

But, are you talking about extracting the full ISO version?
And how would be the setup of the files? (just unpack?)

I used to use WDOSX myself, "back in the days" - but it's not been under development for quite some time.

HX seems to be quite decent and still supported.

char identA[]="Alright, here i am. This is identA where you shall 
look for me using a hex editor or disassembler. Oh yea, and incase you 
forget what this line is, you can use the following password to find me 
faster: 7da33d"; // note: 7da33d is your favorite password.    

C++ is a multiparadigm language; you can write procedural code, object-oriented code, template metaprogramming code... it's speed depends on the code you write (and the compiler), nothing about C++ makes it automatically slower than C.

Nor more secure, really, if you still use libc.

1 What's Wrong With Assembly Language
Assembly language has a pretty bad reputation. The common impression about assembly language programmers today is that they are all hackers or misguided individuals who need enlightenment. Here are the reasons people give for not using assembly:
Assembly is hard to learn.
Assembly is hard to read and understand.
Assembly is hard to debug.
Assembly is hard to maintain.
Assembly is hard to write.
Assembly language programming is time consuming.
Improved compiler technology has eliminated the need for assembly language.
Today, machines are so fast that we no longer need to use assembly.
If you need more speed, you should use a better algorithm rather than switch to assembly language.
Machines have so much memory today, saving space using assembly is not important.
Assembly language is not portable.
These are some strong statements indeed!

Given that this is a book which teaches assembly language programming, written for college level students, written by someone who appears to know what he's talking about, your natural tendency is to believe something if it appears in print. Having just read the above, you're starting to assume that assembly must be pretty bad. And that, dear friend, is eighty percent of what's wrong with assembly language. That is, people develop some very strong misconceptions about assembly language based on what they've heard from friends, instructors, articles, and books. Oh, assembly language is certainly not perfect. It does have many real faults. Those faults, however, are blown completely out of proportion by those unfamiliar with assembly language. The next time someone starts preaching about the evils of assembly language, ask, "how many years of assembly language programming experience do you have?" Of course assembly is hard to understand if you don't know it. It is surprising how many people are willing to speak out against assembly language based only on conversations they've had or articles they've read.

Assembly language users also use high level languages (HLLs); assembly's most outspoken opponents rarely use anything but HLLs. Who would you believe, an expert well versed in both types of programming languages or someone who has never taken the time to learn assembly language and develop an honest opinion of its capabilities?

In a conversation with someone, I would go to great lengths to address each of the above issues. Indeed, in a rough draft of this chapter I spent about ten pages explaining what is wrong with each of the above statements. However, this book is long enough and I felt that very little was gained by going on and on about these points. Nonetheless, a brief rebuttal to each of the above points is in order, if for no other reason than to keep you from thinking there isn't a decent defense for these statements.

Assembly is hard to learn. So is any language you don't already know. Try learning (really learning) APL, Prolog, or Smalltalk sometime. Once you learn Pascal, learning another language like C, BASIC, FORTRAN, Modula-2, or Ada is fairly easy because these languages are quite similar to Pascal. On the other hand, learning a dissimilar language like Prolog is not so simple. Assembly language is also quite different from Pascal. It will be a little harder to learn than one of the other Pascal-like languages. However, learning assembly isn't much more difficult than learning your first programming language.

Assembly is hard to read and understand. It sure is, if you don't know it. Most people who make this statement simply don't know assembly. Of course, it's very easy to write impossible-to-read assembly language programs. It's also quite easy to write impossible-to-read C, Prolog, and APL programs. With experience, you will find assembly as easy to read as other languages.

Assembly is hard to debug. Same argument as above. If you don't have much experience debugging assembly language programs, it's going to be hard to debug them. Remember what it was like finding bugs in your first Pascal (or other HLL) programs? Anytime you learn a new programming language you'll have problems debugging programs in that language until you gain experience.

Assembly is hard to maintain. C programs are hard to maintain. Indeed, programs are hard to maintain period. Inexperienced assembly language programmers tend to write hard to maintain programs. Writing maintainable programs isn't a talent. It's a skill you develop through experience.

Assembly language is hard. This statement actually has a ring of truth to it. For the longest time assembly language programmers wrote their programs completely from scratch, often "re-inventing the wheel." HLL programmers, especially C, Ada, and Modula-2 programmers, have long enjoyed the benefits of a standard library package which solves many common programming problems. Assembly language programmers, on the other hand, have been known to rewrite an integer output routine every time they need one. This book does not take that approach. Instead, it takes advantage of some work done at the University of California, Riverside: the UCR Standard Library for 80x86 Assembly Language Programmers. These subroutines simplify assembly language just as the C standard library aids C programmers. The library source listings are available electronically via Internet and various other communication services as well as on a companion diskette.

Assembly language programming is time consuming. Software engineers estimate that developers spend only about thirty percent of their time coding a solution to a problem. Even if it took twice as much time to write a program in assembly versus some HLL, there would only be a fifteen percent difference in the total project completion time. In fact, good assembly language programmers do not need twice as much time to implement something in assembly language. It is true using a HLL will save some time; however, the savings is insufficient to counter the benefits of using assembly language.

Improved compiler technology has eliminated the need for assembly language. This isn't true and probably never will be true. Optimizing compilers are getting better every day. However, assembly language programmers get better performance by writing their code differently than they would if they were using some HLL. If assembly language programmers wrote their programs in C and then translated them manually into assembly, a good C compiler would produce equivalent, or even better, code. Those who make this claim about compiler technology are comparing their hand-compiled code against that produced by a compiler. Compilers do a much better job of compiling than humans. Then again, you'll never catch an assembly language programmer writing "C code with MOV instructions." After all, that's why you use C compilers.

Today, machines are so fast that we no longer need to use assembly. It is amazing that people will spend lots of money to buy a machine slightly faster than the one they own, but they won't spend any extra time writing their code in assembly so it runs faster on the same hardware. There are many raging debates about the speed of machines versus the speed of the software, but one fact remains: users always want more speed. On any given machine, the fastest possible programs will be written in assembly language.

If you need more speed, you should use a better algorithm rather than switch to assembly language. Why can't you use this better algorithm in assembly language? What if you're already using the best algorithm you can find and it's still too slow? This is a totally bogus argument against assembly language. Any algorithm you can implement in a HLL you can implement in assembly. On the other hand, there are many algorithms you can implement in assembly which you cannot implement in a HLL.

Machines have so much memory today, saving space using assembly is not important. If you give someone an inch, they'll take a mile. Nowhere in programming does this saying have more application than in program memory use. For the longest time, programmers were quite happy with 4 Kbytes. Later, machines had 32 or even 64 Kilobytes. The programs filled up memory accordingly. Today, many machines have 32 or 64 megabytes of memory installed and some applications use it all. There are lots of technical reasons why programmers should strive to write shorter programs, though now is not the time to go into that. Let's just say that space is important and programmers should strive to write programs as short as possible regardless of how much main memory they have in their machine.

Assembly language is not portable. This is an undeniable fact. An 80x86 assembly language program written for an IBM PC will not run on an Apple Macintosh. Indeed, assembly language programs written for the Apple Macintosh will not run on an Amiga, even though they share the same 680x0 microprocessor. If you need to run your program on different machines, you'll have to think long and hard about using assembly language. Using C (or some other HLL) is no guarantee that your program will be portable. C programs written for the IBM PC won't compile and run on a Macintosh. And even if they did, most Mac owners wouldn't accept the result.

Portability is probably the biggest complaint people have against assembly language. They refuse to use assembly because it is not portable, and then they turn around and write equally non-portable programs in C.

Yes, there are lots of lies, misconceptions, myths, and half-truths concerning assembly language. Whatever you do, make sure you learn assembly language before forming your own opinions. Speaking out in ignorance may impress others who know less than you do, but it won't impress those who know the truth.

Why bother with high-level languages? The file ends up being ten thousand times larger than it is supposed to be! Pure assembly language (and pure machine xode) is the best way to go, because you can control all the bytes placed in the file.