C Board - Tech Board

help

Carzon — Fri, 20 Nov 2009 18:33:22 GMT

just 1na 2 know if I can I install 2003 visual studio.net on windows vista and if work..?
ty all...

Bison/Yacc shift/reduce reduce/reduce

AnthonyGould — Fri, 20 Nov 2009 14:15:12 GMT

problem solved - cant find delete button for post

what's the intel pentium processor?

happyclown — Fri, 20 Nov 2009 05:02:58 GMT

Ok, I know the original Pentium from the 90's, but now I think Intel is using "Pentium" again for it's current stable of processors.

There's Centrino, core 2 duo, i7, Atom, which I have no problems with, but now I am starting to see "Pentium Inside" logos. What does Pentium mean in this day and age? I am confused.

Why only boolean? Why not quadlean?

Dino — Fri, 20 Nov 2009 04:42:23 GMT

No, I'm not crazy!!

This thread (http://cboard.cprogramming.com/cplus...ared-java.html) got me thinking about boolean conditions. I know what boolean logic is, and I'm very comfortable with boolean logic. But I wonder if the higher level languages are selling themselves short?

He's my thought process.

I work on mainframes daily. I code a LOT in assembler. In assembler, as some of you must know, you work with condition codes set by individual instructions. On the mainframe, there are two bits used to hold the condition code of condition-code-setting instructions. With these 2 bits you get 4 combinations ("quad") of conditions to test for. Now, not all instructions set all possible conditions, but a lot do, and in assembler, you get to take the branch you need after you've tested for the condition code you desire.

Why is it that this concept of 4 conditions codes (aka 4 possible code paths) has been dumbed down into a true or false in higher level languages?

In assembler to compare two integers, you just compare them. Then, you branch if equal, less than, greater than, or not equal. In C, for example, you compare against EQ, LT, GT, or NE. If I want to test EQ, LT and GT, then that's two compares I have to code. In asm, it would be one compare and then two possible branches. Simpler.

Or, with the above scenario, is the compiler smart enough to see the multiple compares and generate the code that does a single assembler compare and then branch accordingly?

Slackware TTY - that stupid penguin

sean — Sun, 15 Nov 2009 18:55:08 GMT

I'm using a bare bones install of slackware for my mess-with-the-kernel machine. I didn't install X, or anything - so I'm just in the raw tty console. There's a penguin covering the top 5 or 6 lines - and bash obviously expects those lines to be there, because it covers the top of the output from the man pages, vi, etc... How do I get rid of that, anyone know? I could find anything on any other forums or documentation.

Besides - it's a really freaky looking penguin!

edit: Some ncurses programs seem to get rid of it. The menuconfig program for the kernel gets rid of it, but vi doesn't seem to. So I guess my question is how to stop it from showing up at boot...

Help Urgent!!Writing it prac grade 11 tomorrow and need help! SQL and Java

vipur — Sun, 15 Nov 2009 14:45:21 GMT

hey peeps, i have a really big probelemo...i'm in grade 11 and writing i.t p1 prac on monday and still dunno how to call a method from another to a class.....im trying to create a simple program........

Code:

 

public class Display

 {

  void display(String heading)

   {

         System.out.println("My name is bob.");

   }

 }

then call it from this class

Code:

 

public class CallDisplay

 {

  public static void main(String[]args)

   {

         Display print = new Display();

         print.display();

         System.out.print(print);

        }

 }

And i need to know how to use simple sql statements in java....(for example if i were connecting a database from Access into JGrasp.....eg. getNames();

Also i need a few tips on string handling, like how to split or delete strings/characters....

Don't You Hate It When A Plan Doesn't Come Together?

SMurf — Sun, 15 Nov 2009 02:58:51 GMT

Hello,

Well I've spent a good few hours toiling away at this problem and have reached the point where I'm calling it a day (it's 2:58 AM where I am at the moment)...

A few months ago I had an idea to build a mini-ITX based PC that featured a single PCI slot. I have a few cards lying around that I would like to use from time to time, so having a small box to plug them into instead of having to disconnect and haul open the larger tower would be a godsend.

I also "believed" that if I could get one of the last PCI graphics cards to be produced (in this case, a PowerColor Radeon HD 2400 Pro) I could also get it to play back Blu-Ray titles (this budget card doesn't perform H.264 acceleration but does have HDCP). This would mean that it could also serve as a HTPC also.

Of course, I wasn't exactly awash with cash at the time, so I just made a shopping list and saved up. Which brings us nicely to today...

I currently have sat in front of me a Intel D945GSEJT mobo featuring the Atom N270 laptop CPU and 945GSE mobile chipset. It has DVI, SATA and gigabit LAN onboard. It also has a PCI slot. And is completely fanless. :cool:

Acting much the same way as I usually do on Christmas Day, I eagerly tore open the pack containing a 2GB SO-DIMM and slotted the memory in, wired up the case connections and plugged in the 75W external brick power supply. So far so good. I plugged in a monitor and USB keyboard and hit the power button. It's alive! :D

After having a flick through the famously sparse BIOS menus, I then turned the PC off and whipped out the PowerColor. I carefully pressed the card into the PCI slot, changed the monitor connection to the card and flipped the power again...

This time, nothing. :eek:

I turned it back off, removed the card and tried again. Works fine?

I tested the card in my main tower. There was some havoc when Windows XP loaded and found a really slow graphics card in addition to the PCI Express one, but other than that it worked fine.

I scratched my head. The mobo works, the graphics card works... but why not together?

Thinking the board may have a dodgy PCI slot, I tried inserting a video capture card. Booted fine.

Then I remembered that there is an option in the BIOS to select which graphics device to use when booting... but this was missing from this particular BIOS(!)

I frantically tried updating the BIOS to the latest version... no dice.

It seems that the mobo won't boot with the PowerColor installed because Intel have kindly hardwired the BIOS to initialize the onboard graphics first, then it has a look at the PCI slot, tries to initialise the device and locks up because it was not expecting another graphics device to be there.

I know that this is something that Intel have done because a similar mobo with the same chipset but the manufacturer's own BIOS (the MSI IM-945GSE) indicates that you can change the primary video adapter to PCI in the manual. It's just a shame that that board is not widely available (and costs twice as much).

Now, you might be thinking "Don't be sad, cos 1 out of 2 ain't bad", but I just find it really annoying that people still go around crippling things for no good reason and spoiling what would otherwise have been a pretty decent little box. :(

So, for the record then: you cannot use a PCI graphics card with the D945GSEJT. I hope that this info helps anyone else who had a similarly bright idea, and maybe prods Intel into doing the decent thing and repealing this senseless edict with an update.

Now I have a �30 PCI paper weight. Let's hope that someone else out there is using a different board and would like the convenience!

Right, rant over. I'm off to bed.

call a method from another to a class

vipur — Sat, 14 Nov 2009 19:11:08 GMT

Code:

 

public class Display

 {

  void display(String heading)

   {

         System.out.println("My name is bob.");

   }

 }

then call it from this class

Code:

 

public class CallDisplay

 {

  public static void main(String[]args)

   {

         Display print = new Display();

         print.display();

         System.out.print(print);

        }

 }

please help.....eish im stressing lol

Package systems

Aparavoid — Sat, 14 Nov 2009 03:15:36 GMT

In Linux, is it better to use the official package system of your distro or to build from source? Does building from source show in the official package manager or does the user have to track things like that? Why have both?

Open Source RAD GUI tools

abachler — Fri, 13 Nov 2009 13:50:51 GMT

Any recommendations for open source RAD GUI tools similar to LabView?

A unique search need

pkjr04 — Thu, 12 Nov 2009 17:27:20 GMT

I work for a non-profit that sorts and ships donated surplus medical supplies to the developing world. We do all of our sorting and packaging of these supplies donated from hospitals or manufactures via the help of volunteers.

Supplies donated via manufactures are easily handled, as most things are in boxes and labeled. Our problems stem from supplies donated from hospitals. Many of these supplies are unlabeled and little information is given about them.

So, I was wondering, are there any unique search programs out there that could handle the job of searching for these items if we developed our own database? I had the idea of adapting facial recognition software, but that has proved to be too inaccurate (as many products are so irregular in shape and size, it's hard for the program to distinguish) and is way too computer intensive and slow. Additionally, I thought of a question based search process (i.e. What is it made out of? What color is it? How long/wide/tall is it? etc etc) and theoretically having an answer given via a 20 questions approach, but have had a really hard time finding an existing program that already does this.

Does anyone have any suggestions about a searching method that would would well for this purpose? Or know of a program that could preform my latter idea?

SMS

ssharish2005 — Wed, 11 Nov 2009 21:58:42 GMT

Hey guys,

I developing an application where i need to send and receive SMS from a PC. I'm a kinda stuck of were to start. Is there a library/API which i could use. I'm on windows platform.

I know about the AT command approach and the only probably which I'm having is connecting to the device through an hypertermial and i;m not very sure of the AT+CMGW command are supported or implemented as a protocol stack on the device which i have. I suppose i could use few AT command to find if they d support. But before that i need to connect to the device. I use iphone 3Gs.

Or is there a free service which i could use, API ? which connects to the SGRS gateway straight?

Thanks a lot guys!

~ssharish

Comodo Firewall Vulnerability (Port 0)

Mario F. — Wed, 11 Nov 2009 14:56:45 GMT

I was doing today a routine security check on my system. I tend to do these things once a month or so, time permitting. I discovered a Comodo Firewall security hole associated with Port 0.

---
A little background:

Port 0 was supposed to be a non-existing port. An invalid port, or at best a reserved port. However manually made networks packets were always considered well-formed even if targeting or originating from port 0. This because, I think, the original idea was to use port 0 as a wildcard port. Meaning any connection targeting port 0 would allow the client machine network interface to choose any available port "Hey, I have this packet here. It specifies port 0. You choose which port you want this to come in. Just sign here."

Of course, good intentions have been paving the road to hell. And Port 0, while remaining an obscure, and unsupported in most cases, feature is a real port.

Today at least one application actively uses Port 0 based connections for what it is not intended for. That application is iTunes (another security and system stability nightmare people like to install and thus ruin their quiet lives. All because they can't listen to their music anymore on a music player, or at least rip their own music).
---

Back to Comodo:

Port 0 is a valid (if reserved) port. If I have no application on my windows machine actively listening on this port, it will report as being closed to anyone scanning my ports.

And therein lies the rub. A port scan on my machine that includes port 0 will identify my machine and ruin the idea behind stealth ports (closed ports that don't answer back when scanned). So, while Comodo says it offers full stealth mode, it fails doing so on port 0.

Imagine a Radar on your screen. On every sweep of the radar, the hacker is looking for a bunch of IP addresses and scanning their ports. All is silent for a while. The Radar sweaps on your green screen in that circular fashion only radars know how to. It's moments like this that make the internet look like a very lonely place. But suddenly... a very faint bleep. It was my computer saying "Hey! I'm here".
---

Why?

This happens because Comodo Firewall isn't allowing you to set Port 0 in your firewall rules. Despite what it says, you cannot create a rule based on port 0.

The only exception are range-based rules. If you create a rule where you limit access to a range of ports and that range starts at 0, the rule will take effect as intended. But you can't do that most of the time. Port numbers are more often defined individually.

What's worse, Comodo Firewall apparently also ignores port 0 incoming or outgoing connections if a rule doesn't exist blocking it (and the only rule that could was a range-based rule). That is, you will not get a popup on any connections involving Port 0.

---

To make sure of this, I used ShieldsUp Port Probe. You can also use ShieldsUp to scan all your ports and witness with your own eyes Port 0 "closed" stats, instead of "stealth".

EDIT:
If you are using Comodo Firewall like me, or have also confirmed your firewall doesn't support Port 0 based rules, you can try and setup your modem/router firewall, if it comes with a firewall. Many home users on ADSL and Cable modem/routers do come equipped with firewalls and many of them allow you to set port-based rules.

Binary numbers, signed, unsigned.

JOZZY& Wakko — Wed, 11 Nov 2009 11:20:11 GMT

I am trying to read up on binary numbers but I do not fully understand how I can see i a binary number is signed or unsigned.

Could someone explain this for me?

some questions about Boost libraries

Masterx — Sat, 07 Nov 2009 14:53:14 GMT

hello all .
i have just downloaded the latest boost source codes and compiled them, and configured the stuff as i should have!
and then i tried to compile some examples to see how stuff works, and also to check if everything went well! .
one of the examples ran well! but the other one which you can see below, gave me couple of errors!

Code:

#include

#include

namespace bfs=boost::filesystem;

int main()

{

    bfs::path p("second.cpp");

    if(bfs::exists(p))

    std::cout<<p.leaf()<<std::endl;

}

and errors:

Code:

||=== boost example, Debug ===|

obj\Debug\main.o||In function `_Z41__static_initialization_and_destruction_0ii':|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\system\error_code.hpp|205|undefined reference to `boost::system::get_system_category()'|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\system\error_code.hpp|206|undefined reference to `boost::system::get_generic_category()'|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\system\error_code.hpp|211|undefined reference to `boost::system::get_generic_category()'|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\system\error_code.hpp|212|undefined reference to `boost::system::get_generic_category()'|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\system\error_code.hpp|213|undefined reference to `boost::system::get_system_category()'|

obj\Debug\main.o||In function `_ZThn48_NK5boost16exception_detail10clone_implINS0_19error_info_injectorINS_10filesystem22basic_filesystem_errorINS3_10basic_pathISsNS3_11path_traitsEEEEEEEE7rethrowEv':|

)]+0x80)||undefined reference to `boost::filesystem::detail::status_api(std::string const&, boost::system::error_code&)'|

F:\Program Files\CodeBlocks\include\boost-1_40\boost\throw_exception.hpp:(.text$_ZN5boost6system10error_codeC1Ev[boost::system::error_code::error_code()]+0x14)||undefined reference to `boost::system::get_system_category()'|

||=== Build finished: 7 errors, 0 warnings ===|

my question is , how should i know which header file needs which *.lib file!
i think the above errors are due to the absence of a lib file of some kind!
so please help me on this !
and the second question is how can i find more about classes, functions and other useful stuff in boost , just like what we have in C++ Reference [C++ Reference] with examples for each of them , so that i can understand how to use them in my program .
thank you all in advance