C++'s topics - tribe.net

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2009-04-20T16:14:57Z

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posted in C++ - 0 replies

a bit of fun: which is more metal -- C++ or Java?

2008-04-14T18:16:45Z

Hello, all ...

As frivolous an exercise as it may seem, I (developing the client piece of an app) am engaged with a comrade (developing the server piece of the same app) on this topic: Which language is more "metal" e.g. which language would the members of DethKlok (http://www.adultswim.com/shows/metal/) code in, should they choose to?

Defending C++, I submit that it is more metal, due to the following:

1. it has crosses in the name, and everyone knows that crosses are way more metal than coffee
2. C++ developers generally code more to the "metal" (or wire) than Java developers
3. C++ has DESTRUCTORs, which just sounds way more metal than Java's "finalize"
4. C++ can be brutal, with pointers to const members, changing vtables, etc.

My coworker claims that Java is actually more metal, but I can't remember any of his reasons ;-)

Thoughts?

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 4 replies

grr -- anyone experienced in building Firefox plugins in C++, on Windows / OSX?

2008-01-11T09:29:26Z

I feel so stupid. I'm a professional C++ developer, and i've been doing it for years and years. Now I have to write a Firefox plugin (NPAPI) in C++, which sounded easy enough, but after 2 days, I just can't get anything built. The documentation on developer.mozilla.org is often very confusing, a lot of info doesn't seem to be there at all, and i'm growing more frustrated by the day. This is _supposed_ to be easy. Writing an ActiveX control using the ATL in C++ for IE is dead simple to me (i've done it literally dozens of times over the years), but writing a plugin in C++ for Firefox is proving to be quite a frustrating endeavor. Searching the archives of the Mozilla dev-tech-plugins list only shows a few others complaining like I am, with no responses offered. The samples in the mozilla tree don't seem to build much of anything, no DLLs / bundles are generated on Windows / Mac OSX (the two platforms I need to target the most) ... sigh.

Can anyone point me to a code sample (hopefully simple for the obviously brain-dead developer I am) for a Firefox plugin that is known to build on Windows and OSX? What steps did you take to build it, and how did you install it?

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 3 replies

My friend was asking about C++ in Linux

2007-12-01T00:21:53Z

He was wanting to know what is the best IDE possibly similar to Microsoft's Visual Studio for doing Linux based C++ development? I didn't have a good answer.

posted in C++ - 4 replies

how to code the deblur image algorithm

2007-11-21T10:57:27Z

Hi All,

I am studying about the deblur image algorithm to deblur a blurred image. It uses blind deconvolution algorithm.

In the Matlab, deblur image is showing :
1) Create Point Spread Function (PSF) that Gaussian is usually used.
2) using Deconblind function = blind deconvolution to deconvolve blurred image with PSF.
............

So i am in the process of translating my matlab code into C to run on the Parallel system.
I was wondering if there are C function available for these process (deconvblind).

Anyone have any ideas on this ???

Thank you,

posted in C++ - 0 replies

Question

2007-05-01T10:04:26Z

For the programmers who prefer C++ over other PL. why do you prefer C++.
just curious

posted in C++ - 22 replies

1099 issues

2007-04-27T23:14:44Z

So how do you guys handle your taxes? I'm so confused!

posted in C++ - 2 replies

Please help ASAP / File I/O displaying graph

2007-04-03T21:33:54Z

Please have a look at the following code:

---------------------------------------------------------------------------------------------------------

#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>

void printMonth(int month);
void PrintaLine(int, char);
void SkipLines (int);
void indent (int);

// PRECONDITION: month holds an integer 1-12
// POSTCONDITION: the corresponding month (Jan, Feb, ..., Dec) has been
// printed to the standard output.

ifstream infile1("input1.txt");
ifstream infile2("input2.txt");
ofstream outfile("output.txt");

int main()
{
string month[12];
double rainfall[12]; //this year's rainfall for each month
double averages[12]; //average rainfalls for each month
int currentMonth; //what month is it? 1-based

//
// Get the average rainfall for each month, Jan-Dec
//
// Read the in put files 1 and 2
for (int i=0; i<12; i++)
{
infile1 >> month[i] >> rainfall[i];
}
for (int j=0; j<12; j++)
{
infile2 >> month[j] >> averages[j];
}
PrintaLine (65, ':');
indent(10);
outfile << "The table shows the month avge and the diff\n";
PrintaLine (65, ':');
SkipLines(3);
outfile << setw (20) << setiosflags (ios::left) << "Months"
<< setw(20) << "Actual" << setw(20) << "Average"
<< setiosflags(ios::right)
<< setw (10) << "Difference" << endl;
SkipLines(1);
for (int i=0; i<12; i++)
{
outfile << setw (20) << setiosflags (ios::left) << month[i]
<< setw(20) << rainfall[i] << setw(20) << averages[i]
<< setiosflags(ios::right)
<< setw (10) << rainfall[i] - averages [i] << endl;
}
SkipLines (2);
outfile << "Negative sign in the Difference shows the Actual Rainfall is below Average Rainfall\n";
}

void PrintaLine(int n, char c){
for (int i=1; i<=n; i++)
outfile << c;
outfile << endl;
}

void SkipLines (int n){
for (int i=1; i<=n; i++)
outfile << endl;
}

void indent (int n){
for (int i=1; i<=n; i++)
outfile << ' ';
}

-------------------------------------------------------------------------------------------------------

This displays the table of the monthly rainfall and the avg. monthly rainfall and the diff. to the file output.

Now I want to do the following:

INTERACTIVE DISPLAY.

All files have been closed, ask the user if they want to analyze the data. If they say yes, ask if they want to see it in tabular or graphic output form (refer to Display 7.8 for how to do this). Ask what data they want to see (average, actual, divergence of actual from average).

Please reply me ASAP as I due my assignment soon

posted in C++ - 0 replies

OSX coding

2007-02-11T04:40:06Z

Hello,
I used to code quite a bit. Using C++ and opengl on a windows platform. Its been many years and now I use OSX.
I want to start coding again and I want to build a fairly simple but extentable text editing program.
I am wondering what language i should use. Since i used to code in c/c++ i am hoping to do that. So i am also wondering if there are some libraries to help with the font and graphic display on OSX that people are really excited about.
I am asking this on the tribe, in the hopes that someone might be really excited about a newish way of doing things like this.

Thank you,
Luke

posted in C++ - 3 replies

libjpeg crash when supplying user colormap

2006-11-21T20:54:59Z

So, this isn't a c++ question (again), but this tribe seems the most useful for s/w development questions.. :)

I'm using libjpeg to decode images, but I am experiencing a strange crash when having the library deliver 8bit color data with a colormap I am supplying. The crash doesn't happen during decode, but in the libjpeg memory manager during shut down of the decoder (both jpeg_abort() and jpeg_destroy_decompress()). I've tried not using the libjpeg allocator for the colormap memory, but that doesn't change the behaviour.. any tips would be appreciated..

peace
-cpr

posted in C++ - 4 replies

package a set of dlls into a single binary

2006-11-21T00:22:39Z

I would like to compile a binary on CygWin and somehow merge it and its dependancies into a single binary for a private project Im working on (not for redist.) Does anyone know of a utility that can take multiple binaries, merge them to a single file, and fix-up any linkages so it works as a standalone library? It would simplify my project immensely...

posted in C++ - 0 replies

thumpin'

2006-11-10T16:50:11Z

... so here we are, suddenly in the minority. What brought us here, after such a meteroric ascension to power a little over a decade ago? We were the party of responsibility (we "delete" what we "new"), of limited executable size (no VMs to carry around), of conservation of system resources (don't hog the CPU, be lean with memory, be as light on the wire as you can). We preached doing your own memory management, we stressed design patterns, we had all of the answers that the world needed to develop truly great software.

So what happened? We've lost our way. Garbage collection libraries, very high-level class libraries that added dozens of function calls to a typical call stack before it got to libc / libc++, cheap RAM, broadband, really inexpensive multi-gigabyte hard disks, super-fast CPUs ... we grew just as slow and bloated as that which were were rallying against, not to mention more fractured with every new platform we coded for ("OLE / [D]COM! No, DO! No way, CORBA!"). We came to change development, and development changed us. The Java programmers have taken over, with their garbage collectors, GUI toolkits, IDEs, RMI, XML-on-the-wire and resource-consuming VMs ... and we've lost our way.

Now is the time to step back, examine our ascension and declension, and re-affirm ourselves to the core principles we believe in. Just yesterday, I fixed a file seek / write bug in my code :-)

Regards,

John, winking

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 0 replies

C++ way of setting file position for file sizes larger than 32-bits?

2006-11-08T07:55:04Z

Hello, all ...

I need to create a file and set it to a specific size (the idea being that there is another thread that uses std::ofstream::seekp() to write blocks to the file as they arrive off of the network, likely out of order, so if the 10th block of the file arrives before the 1st, I need to be able to handle it). The thing is, std::ofstream::seekp() doesn't seem to allow me to seek past the end of the file and set the file position there e.g. it sets the failbit true if I try. In C, I used to do this with feek(), so I could code something like this:

fseek( pFile, 10000000, SEEK_SET ); // makes the file 10000000 bytes long if it was shorter before

... but fseek() expects a long for the seek position, and this is 2006, where a long isn't big enough (files could be much larger than 4G). I have to do this in a portable way (Windows and Mac OSX / *nix).

Ideas?

Regards,

John, looking for a simple solution

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 1 reply

socket issues?

2006-10-30T22:18:36Z

Hello, all ...

Like many of us i'm sure, i've done my share of sockets (either BSD or WinSock) code. It's usually not so hard. I'm chasing a bug right now, though, which has got me wondering about some questions that I thought I knew:

Does recv() _only_ return 0 if the server closed the connection? Does setting the socket as blocking or non-blocking matter change this at all? Does select() work differently on non-blocking vs. blocking sockets?

My understanding is this:

1. If select() sets the FD / socket in the input set, it's ready to be read.
2. If recv() is called on the FD after select() sets it, and it returns a positive #, that # is the # of bytes read from the socket.
3. If recv() is called on the FD after select() sets it, and recv() returns 0, the server closed the connection.
4. If recv() is called on the FD after select() sets it, and recv() returns -1, an error occured ... if errno / WSAGetLastError() is set to EAGAIN / WSAEWOULDBLOCK, then the server is still there, it has just not sent anything yet. This should only happen if the FD / socket is set to non-blocking mode (otherwise recv() will block).

Is my understanding flawed? I'm seeing recv() return 0 (blocking and non-blocking) very often (i'm sending an HTTP request to Apache to get a block of data e.g. a range request, and if recv() returns 0 only if the server disconnected, then it's disconnecting very often before it sends the entire range I requested). This behavior varies by time of day, file requested, etc. which suggests that Apache is loaded and dropping me, but others stress that it doesn't do that, or at least, not anywhere near as often as I seem to be seeing. I would expect recv() to return -1 and have errno / WSAGetLastError() set to EAGAIN / WSAEWOULDBLOCK if the server is busy, but no ... recv() just returns 0.

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 1 reply

MSVC.NET 2005 and std::stringstream ... grrrr

2006-10-18T23:59:46Z

Hello, all ...

I'm finding that MSVC.NET 2005's stringstream (and o / i variants) leak memory when used as parameters (passing them by reference to other methods). I'm facing the possibility of rewriting all of our code that uses them to use something else (the few that i've replaced with -- ugh -- const char *, have resulted in less leakage) ... has anyone else seen this? Also, our code has to be portable across Win32 and Mac OSX (*nix), so we would like to keep platform-specific solutions to a minimum, so we're all about using the C++ library, STL, Boost, stuff like that.

Grrrr.

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 7 replies

template hell!

2006-09-19T04:07:10Z

Hello, all ...

I've been doing templates for years (either using others' templates or making my own), but this is the first time I need to make a library that implements a template class. Here is my sample:

template1.h

// class templates
#include <iostream>

template < class T > class pair
{
private:
T a, b;
public:
pair (T first, T second);
T getmax ();
};

template_total.cpp

// class templates
#include <iostream>
#include "templates1.h"

template < class T > pair< T >::pair( T first, T second )
{
a=first; b=second;
}

template < class T > T pair< T >::getmax ()
{
T retval;
retval = a>b? a : b;
return retval;
}

int main ()
{
pair <int> myobject ( 100, 75 );
std::cout << myobject.getmax() << std::endl;
return 0;
}

... now when I compile this with gcc4.0.1 (on Mac OSX 10.4.7), this is what I get:

PugsleyButt:~/devstuff/c++/templates jmzorko$ c++ templates_total.cpp -o templates_total
PugsleyButt:~/devstuff/c++/templates jmzorko$ ./templates_total
100

... which is correct. Now I want to make a library with the template class and implementation, and use that library:

PugsleyButt:~/devstuff/c++/templates jmzorko$ cat templates1.h
// class templates
#include <iostream>

template < class T > class pair
{
private:
T a, b;
public:
pair (T first, T second);
T getmax ();
};

PugsleyButt:~/devstuff/c++/templates jmzorko$ cat templates1lib.cpp
// class templates
#include <iostream>
#include "templates1.h"

template < class T > pair< T >::pair( T first, T second )
{
a=first; b=second;
}

template < class T > T pair< T >::getmax ()
{
T retval;
retval = a>b? a : b;
return retval;
}

PugsleyButt:~/devstuff/c++/templates jmzorko$ c++ -c templates1lib.cpp -o templates1lib.o
PugsleyButt:~/devstuff/c++/templates jmzorko$ ar rcs libtemplates1.a templates1lib.o
PugsleyButt:~/devstuff/c++/templates jmzorko$ ll
total 44
0 drwxr-xr-x 9 jmzorko jmzorko 306 Jul 15 04:40 .
0 drwxr-xr-x 48 jmzorko jmzorko 1632 Jul 15 04:29 ..
4 -rw-r--r-- 1 jmzorko jmzorko 2192 Jul 15 04:40 libtemplates1.a
4 -rw-r--r-- 1 jmzorko jmzorko 156 Jul 15 04:11 templates1.cpp
4 -rw-r--r-- 1 jmzorko jmzorko 149 Jul 14 17:51 templates1.h
4 -rw-r--r-- 1 jmzorko jmzorko 244 Jul 15 04:10 templates1lib.cpp
4 -rw-r--r-- 1 jmzorko jmzorko 1980 Jul 15 04:40 templates1lib.o
20 -rwxr-xr-x 1 jmzorko jmzorko 20040 Jul 15 04:34 templates_total
4 -rw-r--r-- 1 jmzorko jmzorko 340 Jul 15 04:34 templates_total.cpp
PugsleyButt:~/devstuff/c++/templates jmzorko$ nm libtemplates1.a

libtemplates1.a(templates1lib.o):
00000094 s EH_frame1
0000007c s __GLOBAL__I_templates1lib.cpp_1FD5A050_803EC32C
00000100 s __GLOBAL__I_templates1lib.cpp_1FD5A050_803EC32C.eh
00000024 s __Z41__static_initialization_and_destruction_0ii
000000d8 s __Z41__static_initialization_and_destruction_0ii.eh
U __ZNSt8ios_base4InitC1Ev
U __ZNSt8ios_base4InitD1Ev
00000140 b __ZSt8__ioinit
U ___cxa_atexit
U ___dso_handle
U ___gxx_personality_v0
0000013c S ___i686.get_pc_thunk.bx
00000000 t ___tcf_0
000000b0 s ___tcf_0.eh
PugsleyButt:~/devstuff/c++/templates jmzorko$

... well, I don't see anything that indicates that the template is in the library (libtemplate1.a), but i'll try making code that uses it anyway and see what happens:

PugsleyButt:~/devstuff/c++/templates jmzorko$ cat templates1.cpp
// class templates
#include <iostream>
#include "templates1.h"

int main ()
{
pair <int> myobject (100, 75);
std::cout << myobject.getmax();
return 0;
}
PugsleyButt:~/devstuff/c++/templates jmzorko$ c++ templates1.cpp -L. -ltemplates1 -o templates1
/usr/bin/ld: Undefined symbols:
pair<int>::getmax()
pair<int>::pair(int, int)
collect2: ld returned 1 exit status
PugsleyButt:~/devstuff/c++/templates jmzorko$

... and that's the problem -- when I put my template class and implementation in a library, I can't use them from anywhere else. I know that templates are difficult for a C++ compiler, but how do I solve this? BTW, this code fails the same way on Windows, so once I know what the real problem is and how to fix it on *nix, i'll find the MS equivalent way to fix it ...

Has anyone else run into this? I know it's a common problem ...

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 19 replies

Floating point woes

2006-09-05T19:26:35Z

I'm writing a few short programs based on calculating factors in electronics.

As such, I often have to multiply and divide some small numbers, and the round-off is of such a magnitude that it renders the calculations useless.

For instance, with this fragment of code:

#include <iostream>
using namespace std;
int main () {

double test;
test = ( 1 / 10000) + ( 1 / 200000);
cout >> test;
return 0;
}

The output will give me zero.

posted in C++ - 2 replies

Need a C++ Jock

2006-08-09T19:01:57Z

Hi all,
I work for Shutterfly and we're looking for someone who is a very strong C++ programmer. Shutterfly pays very well and has great benefits. We're located south of San Francisco in sunny Redwood City. If you're interested, please send me a message!

posted in C++ - 0 replies

creating 90 degree perpendicular lines

2006-07-31T19:59:35Z

this is not c++ specific, and I am working in c to implement it, but, I am starting to work on gradient fill routines, and for the linear version I need to draw lines perpendicular to the fill path. so, given a line from x1,y1 to x2,y2, how to I calculate end points for all of the perpendicular lines (one per pixel along my fill path)? any takers? hehe.. :)

posted in C++ - 9 replies

using the preprocessor to do something N times

2006-07-30T21:36:29Z

Is there a c++ preprocessor instruction to repeat something a number of times?

I am doing some loop unrolling and I would like to do something like this (making up my own preprocessor command :P)

#repeat 16
x += p[a++];
#endrepeat

posted in C++ - 4 replies

C#

2006-07-30T01:03:00Z

Anyone here a fan of C#? I was talking to a programmer friend and he was saying that C# is going to largely replace C++ in the coming years.

posted in C++ - 11 replies

smart pointer for unsigned char[]?

2006-07-15T19:14:37Z

Hello, all ...

I want to use a smart pointer, preferably boosty, to encapsulate an array of unsigned chars that I need to allocate from the heap:

int main()
{
unsigned char *pBuf = new unsigned char[ 512 * 1024 ]; // icky, this isn't quite smart enough :-)

auto_ptr< unsigned char * > pBuf( new unsigned char[ 512 * 1024 ] ); // no work, auto_ptr dtor does not call delete[]

boost::scoped_array< unsigned char *> pBuf( new unsigned char[ 512 * 1024 ] ); // no work, boost expect an array of unsigned char pointers here, not an array of unsigned chars

// the thing I kinda need to do is ...

fread( pBuf, 1, lotsa_bytes, pFile );
}

... any hints? I'm not new to smart pointers, but I am kinda new to boost ...

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 5 replies

FILE * from std::ofstream?

2006-06-15T05:55:23Z

Hello, all ...

I need to interface a library that expects to communicate through a FILE * to my code written using ofstream. In these endeavors, I would like to just have my ofstream return a FILE * that this library can use, but I don't see how I can do that. The ofstream.rdbuf() returns a basic_filebuf, but there seems to be no way of getting a FILE * from it in a cross platform way (this code has to work on Mac OSX, using gcc, as well as Windows, using the MSVC.NET compiler).

Am I doomed to a C-style interface to my lower level file objects, just because this library expects a FILE *? I'm sure i'm not the only one who has run into this ...

Regards,

John

Falling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 3 replies

query_string

2006-05-29T20:47:44Z

I am trying to program cgi with c++ and having a hard time
filtering text data for specific patterns( field names and data)
from the 'query_string' .
string s(getenv("QUERY_STRING"));
i recieve my string from html forms and the string will look something like
first=Fred&last=Chimp&color=Blue
assuming i the forms in the html document ask the user for their first name, last name and favorite color.
I need to go through this string and get user information and then send it back to the user for display. Any ideas on how i can accomplish this? A nudge in the right direction would be great! Huge thanks in advance!

posted in C++ - 11 replies

Tracking an IP adress?

2006-05-27T05:31:27Z

I downloaded CommView and I am not sure what this means:

Maximum packets in buffer – sets the maximum number of packets the program stores in the memory and can display in the packet list (2nd tab). For example, if you set this value to 3000, only the last 3000 packets will be stored in the memory and packet list. The higher this value is, the more computer resources the program consumes.

What is a packet?

Also I tried installing the Driver for Dial ups and it says it is not compatible with WAN Miniport (IPX) <which is what I have it on my computer …. What will happen if I change it?

Does anyone know how to use this and can explain it someone who knows nothing about the deeper aspects of computers?

Thank you in advance! Very much!

xo

ps: What is a "string" and a "hex".... please keep in mind I know nothing really about this, I am just looking for ways to track IP adress traffic on my computer.

Thnx again!

posted in C++ - 3 replies

Computer program for language, quick and easy?

2006-05-27T00:17:11Z

I am not sure if I am posting this in the right tribe, but is there a software that I can get whereby if I type in, say the word, "Time", or sentance, "What time is it?", that it will tell me how to write and say it in another language?

Thank you so much!

posted in C++ - 3 replies

word count

2006-05-01T20:06:24Z

I wrote a program counting word from a string a user inputs but i am having a hard time figuring out how to go back and count the number of characters in each word and then avreaging that out. any help anyone can provide would be appreciated.
Thanks
my program goes as follows
#include <iostream>
#include <cctype>
using namespace std;

int wordCount(char * , char);
int word;

char userString;

int main()
{
const int size = 81;
char userString[size];
cout << "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~"<<endl;
cout <<endl<< "Enter a string of up to 80 characters: "<<endl<<endl;
cin.getline(userString, size);
cout << " The number of words in that string are: ";
cout << wordCount(userString,size) <<endl;
cout << " The average words in this string are: ";
cout << word<<endl;
return 0;
}

int wordCount(char *strPtr , char word)
{
int index =1;
while(*strPtr != '\0')
{
if(*strPtr == ' ' )
index++;
strPtr++;

}
return index;

posted in C++ - 1 reply

IP address -- std::string to hex

2006-02-28T04:19:43Z

Hello, all ...

I'm wondering what the best / least # of lines way in C++ (so it's ok to use C++-isms like iostream, fstream, string, etc.) is to convert an IP address in dotted format (stored in a std::string) to an IP address in hex (stored in an array of chars)?

No, this is not a homework question -- i'm just in the middle of writing something like this (to search an ethereal dump file for RTP packets coming from a certain address) and want to know how _you_ would do it :-)

Regards,

John

Faling You - exploring the beauty of voice and sound
http://www.fallingyou.com

posted in C++ - 4 replies

convolution and fft

2006-02-06T21:21:03Z

Hi all;

So, I'm in the process of translating my matlab code into C to run on a parallel system. I'm brand spankin' new to C but have be coding in matlab for about 18 months. In my current code, I transform my data through use of convolution and fft. Matlab has built in functions for these manipulations. As I'm not one for re-inventing the wheel, I was wondering if there are C functions available for these two processes (convolution and fft)? I have some information about how to write these functions up but it would be, of course, easier if these functions exist in some library that I could just add to my program.

Anyone have any ideas on this?

Thanks.

Alan

posted in C++ - 4 replies

Trouble with strcat

2006-02-03T04:32:04Z

I am writing a program in C but I am getting an error when it compiles that doesn't make any sense:
Warning: passing argument 1 of 'strcat' makes pointer from integer without a cast.

The relevant bits of code are:
The variables:
char da = 'A';
char db = 'C';
char dc = 'G';
char dd = 'T';
char dna1 [100000];

Where the error appears:
if(random == 1)
strcat(da, dna1);
else if (random == 2)
strcat(db, dna1);
else if (random == 3)
strcat(dc, dna1);
else
strcat(dd, dna1);

It doesn't like strcat for some reason. Both are chars, so it *should* work as far as I can tell.

Anyone have any suggestions to a c newbie?

Thanks!

posted in C++ - 9 replies

Macintosh and C question

2005-12-14T02:57:24Z

So, I'm in the process of learning C. I have about a year and a half of programming experience in Matlab.

I'm working through Brian Kernighan's "The C Programming Language" and I keep running into problems with my programs hanging. They compile just fine but I don't get any output. It's as if they're caught in a loop they can't get out of. I've double checked my code and it looks just fine (coming from the book).

Anyone have any ideas? I'm working on a Mac G4 and compiling using gcc in unix. Love to hear any ideas.

posted in C++ - 4 replies

what's the best C++ website??

2005-11-22T18:58:18Z

I'm just a C++ newbie. I'm majoring in programming and I'm currently in my first C++ class. I was just wondering what everyone's favorite and/or most useful C++ site is.

posted in C++ - 8 replies

Looking for C++ proggies in Santa Cruz.

2005-10-10T20:57:36Z

If you have any interested in working on a high-profile, next-gen console video game, please send your resume to resumes@santacruzgames.com

Rock on.

MAZ

posted in C++ - 0 replies

Codase: a syntax-aware source code search engine

2005-09-16T04:02:00Z

After a few years work on programming language
compilers, decompilers and translators, I finally
launched an alpha version of a website for developers
to find code snippets easily. It contains over 100M
loc of c/c++ code. The search is syntax aware, so you
can easily find method calls and class definitions,
etc. I'd like to hear some feedback.

Our web site is at http://www.codase.com.

posted in C++ - 0 replies

Massive C/C++ source repository

2005-09-16T04:00:17Z

http://csourcesearch.net/

"Searching 110,066,601 lines of C/C++ code"

posted in C++ - 2 replies

interesting, incredible, intriguing

2005-09-06T15:49:20Z

if you can program

i have a proposition for you

it promises to be all of those three above words.

get back to me.

posted in C++ - 5 replies

Dev Advice, if anyone may. Please.

2005-08-24T05:52:02Z

Hi,

If I may ask for your advice :

I would like to dev from Bottom Up an app.

It has to have scalability in user number.

Real time elements integration.

And tools that can me added, modified and or upgraded as you go.

MySQL back end.

Simple interface.

Do YOU think that Lisp is a good choice ?

What is the learning curve for it if you could give even an erroneus evaluation of a rate.

1 - 12 months.

Any other app for a better, quicker solution.

Thank you for your patience.

Lazlo.

posted in C++ - 14 replies

lost in strings

2005-08-23T07:35:59Z

I have a program that I know I need a string to use. Problem is in class we did a program with strings in which we input one name like "Dan" and another name like "dave" and it would say which is bigger, how many characters are in each ect. This new program I have to ask the user to input a sentence like.. " This book has ten pages" then it would count the number words and senteces in text. Also I would have to ask the user for a letter like "a" and it would count the lower and upper case letters. I have a program in VB where i would put "Hello" and it tels me how many times "L" is used. (i cant find that disk )

I have seen programs in which they count words from text from a file. The program needs to work like microsoft word (where when you go to word count it tells you all those things).

posted in C++ - 6 replies

i need arrays boss @_@

2005-06-29T02:54:24Z

simply put my program is suppose to be able to input 20 names and ages..then when it compiles it suppose to list the names in alphabetical order. Now I did something like this but it wasnt woth names it was with numbers. Then the program is suppose to save on a txt file.I used the same exact program that i did in class. I hardly changed the data. I compile it..it says "linker error." Also is my code correct for putting characters in alphabetical order...the internet wasnt much help with that. Anyone help me out..here's my code...

#include<iostream.h>
#include<string.h>
#include<iomanip.h>
#include<fstream.h>
void main()
{
int sku[10];
char description[10][25];

//prototypes
int input ( int [ ], char[ ][25]);
void report( int [ ], char[ ][25]);
void savedata( int [ ],char[ ][25]);
void sort( int [ ], char[ ][25]);

//functions
input( sku, description);
sort( sku, description);
report( sku, description);
savedata( sku, description);
}// close main

int input( int sku[ ], char descr[ ][25])
{
int n=0;
char answer;

do {
cout << "\nEnter the age: ";
cin >> sku[n];
cout << "\nEnter the name: ";
cin >> descr[n];
n++;
cout << "\nDo want to enter another name? (y/n) ";
cin >> answer;
}while( answer == 'y' || answer == 'Y' );
return n;
}//close input

void report( int sku[ ], char descr[ ][25], int n)
{
int i;
void drawline(char , int );
drawline( '_',70);
cout << setw(7) << "age"
<< setw(25) << "Description"
<< '\n';
drawline( '_',70);
for( i = 0; i <= n-1; i++ )
{
cout << setw(7) << sku[i]
<< setw(25) << descr[i]
<< '\n';
}//close for
drawline( '_',70);
}//close report
//drawline() definition
void drawline(char c, int m )
{
int counter=1;
while ( counter <= m )
{
cout << c;
counter++;
}//close while
cout << '\n';
}//close drawline

void savedata( int sku[ ], char descr[ ][25], int n)
{
int i;
ofstream outfile;
outfile.open("a:names.txt", ios::app );

for( i = 0; i <= n-1; i++ )
{
outfile << sku[i]
<< ' ' << descr[i]
<< '\n';
}//close for

outfile.close();

}//close savedata
void sort( int sku[ ], char descr[ ][25], int n)
{
int i, j, temp;
char tempdes[25];

for( i = 0; i <= n-2; i++ )
{
for( j = i+1; j <= n-1; j++ )
{
if( descr[ j ] < descr[ i ] )
{
temp = sku[ i ];
sku[ i ] = sku[ j ];
sku[ j ] = temp;

strcpy( tempdes , descr[ i ]);
strcpy( descr[ i ] , descr[ j ]);
strcpy( descr[ j ] , tempdes);
}//close true branch
}//close f for loop
}//close i for loop
}//close sort

posted in C++ - 1 reply

need quick help

2005-06-23T00:28:29Z

im making a program that wil list the trig functions by increments of 10..and i dont have a compiler program. I am using Visual Studio.NET

#include <iostream.h>
#include <math.h>

void main

float degrees, Sin, Cos, Tan;

cout << "Enter a number of degrees: ";
cin >> degrees;

cos = cos(degrees*180/3.14);

cout << "Cosine: " << cosine << endl;
cout << "Sine: " << sin(degrees*180/3.14);
cout << "Tangent:" << tan(degrees*180/3.14);

do {

cout << "Enter degrees: ";
cin >> degrees;
cout << "Sin";
cin >> sin;
cout << "Cos";
cin >> Cos;
cout << "Tan";
cin >> Tan;

counter = degrees;
cout << setw( 10 ) << "Degrees"
<< setw ( 20 ) << "sine"
<< setw ( 20 ) << "cosine"
<< setw ( 20 ) << "Tangent"
<< "\n";
while( counter <= Sin, Cos, Tan)
{
cout << setw( 10 ) << degrees
<< setw ( 20 ) << sine, cosine, tangent
<< "\n";
counter = counter + 10;

}// end while
cout << "\nDo you want to do this again?(y/n) ";

}// end main

when its done its suppose to look like this..

Degrees Sin Cos Tan

with the list of degrees from 0-360 and the sin, cos and tan of that degree.

posted in C++ - 8 replies

Programming Jobs Losing Luster in U.S.

2005-06-20T22:23:46Z

http://news.yahoo.com/news?tmpl=story&cid=562&e=4&u=/ap/tech_job_decline

posted in C++ - 4 replies

Brew Your Own Beer? Write Software?

2005-06-16T21:15:55Z

Hi all,

I'm looking to get one or two more programmers involved in an open source project a couple friends and I have started.

We're creating a cross-platform homebrewing app. Come on....software and beer? What could be better. ....Something similar to ProMash (downloada demo at www.promash.com) ... but with a better interface, more userfriendly, modern features and well, it won't just work on Windows... I'm a Mac user myself, and another one of us is a Linux guy, so...

Just send me a mail if you're interested...or just curious....

Remember...open source...all fun, no pay for any of us....we're doing this b/c we like to. It'll be free software....like Firefox.....just not as popular.

posted in C++ - 1 reply

need help

2005-06-14T22:28:18Z

i need to make a program in which I nned to make a table with sin, cos, and tan functions from 0 - 360. I know Iam suppsoe to use M_pi...but im not getting much with that...im getting errors.

Also I have to act as if i work for the phone company and output several call durations "such as 45,43,12,17,78"

and I have to categorize them as "shorstest call, longest call, count the total number of calls made and the avergage of a call on the list"

for this one i have this:

#include<iostream.h>
#include<iomanip.h>
main()
{
int a, b, c,d,e,f;

do {

cout << "Enter first call: ";
cin >> a;
cout << "Enter second call: ";
cin >> b
..you get the idea

cout << "Enter longest calls made: ";
cin >> a;
cout << "Enter shortest calls made: ";
cin >> b
similar as before

This is so damn troublesome...im a wreck with these programs..

posted in C++ - 5 replies

kind soul to help w/ homework?

2005-05-06T01:03:55Z

Out of ideas…
Hello. I’ve been working on a program for a class (and using a class at that) that translates prefix to postfix using a LinkedList stack. We are supposed to create a stack class & use it to perform the task. My solution is not eloquent, but I can’t even find out IF it will work because it won’t compile, even after many rounds of “The power of Christ compiles you!” *sigh*

I’m using .NET environment for first time (it really isn’t winning me over) & wondering if its related? I get this error message:
“error C2227: left of '->TopFlag' must point to class/struct/union” paired with “error C2819: type 'stackType' does not have an overloaded member 'operator ->'” for each line where I referece my class object (mystack). It seems clear it isn’t recognizing my class object, but I don’t know why – i.e. error in declaration, error with linking.

The class files compile fine, but when I try to compile whole project it crashes. The instructor has looked at it & says “I ‘dunno” *grrr* it’s a small program.

Any chance someone out there would take a look at it & see if something jumps out? I can email text or .cpp files. Thanks a ton,
Rihanha

posted in C++ - 2 replies

Reference

2004-09-16T02:40:59Z

So I've got my trusty K&R if I forget my syntax for vanilla C, but I don't have the budget for any more books. Is there someplace online I can look up the meanings of things like -> or :: if I can't remember?

posted in C++ - 2 replies

Mentors

2004-08-22T18:23:39Z

hi everyone I'm in desperate search for some one who would be willing to help me learn how to do some programming. I've already bought a ton of books, but unfortunatly through them I learned that I am the type of person who can't learn through books alone.....you can't really ask them questions and get anwsers.so I was just wondering if enyone out there would be interested in mentoring me, either via internet or if your located within the Sea-Tac area perhaps getting together in person.

posted in C++ - 12 replies

help a newb with recursion?

2004-07-24T18:54:12Z

hullo folks, first post on these boards. I'm learning c++ currently, and am working on an assignment with recursion.

the assignment is to write a recursive function named reverseWithinBounds, that has an argument that is an array of characters and two arguments that are bounds on array indices. the function has to reverse the order of those entries in the array whose indices are between the two bounds. so for example, if the array is
a[0] == 'A' a[1] == 'B' a[2] == 'C' a[3] == 'D' a[4] == 'E'

and the bounds are 1 and 4, then after the function is run the array elements should be:

a[0] == 'A' a[1] == 'E' a[2] == 'D' a[3] == 'C' a[4] == 'B'

i wrote mine so that the user can enter his own word and bounds, i opted to set it up for use with the word 'partytime'. here's my code -

#include<iostream>

using namespace std;

void reverseWithinBounds( char x[], const int bound1, const int bound2 );

int main()
{
char x[10];
int bound1, bound2;
char ch;

cout << "enter a nine letter word: " << endl;
for( int i = 0; i < 10; i++ ){
cin.get(ch);
x[i] = ch;
}
cout << "enter the first bound: " << endl;
cin >> bound1;
cout << "enter the second bound: " << endl;
cin >> bound2;

for( int j = 0; j < bound1; j++ )
cout << x[j];
reverseWithinBounds( x, bound1, bound2 );

return 0;

}

/******************************************************************/

void reverseWithinBounds( char x[],
const int bound1,
const int bound2 )
{

int i = bound1;
if( x[i] != '\n' ){
reverseWithinBounds( x, bound1, bound2 );
cout << x[i];
i++;
}
}

it compiles fine, it gets the information fine, but when it gets to the reverseWithinBounds function, it just shuts down. I'm sure it's something obvious causing the problem, I have a tendency to not see obvious problems ( occam and i are not friends )

greatly appreciate any help

posted in C++ - 2 replies

sorry, more home work!

2004-05-31T20:34:51Z

having issues with using the cin.getline funtion. Am i putting it in the wrong place or am i doing something else wrong?

cout<<"Enter Coordintates of polygon (seperated by commas) " << endl;
cin >> coor;
cin.getline (coor, 100);
strtok (coor, ",");
while (tokenPtr != NULL)
{cout << tokenPtr << '\n';
tokenPtr = strtok (NULL, ",");
cout<<coor;
}

Any help is appriciated...

posted in C++ - 7 replies

C# Programmer for our Company

2004-05-28T07:10:10Z

Pasadena CA. based company seeks a programmer to write a small code for our development

posted in C++ - 1 reply

Pointer-to-function casting

2004-05-09T07:19:01Z

Do you thing the following is correct C++?

int foo (char * str); // an arbitrary function
void * p = foo; // store PTF as void *

There is an interesting discussion about this at http://www.relisoft.com/forum/toast.asp?sub=show&action=posts&fid=5&tid=2827 .

posted in C++ - 4 replies

the newb says high

2004-04-13T17:59:43Z

Hey all, i just started a C++ class at my college and found that even though the last time i took a programming clas was QBasic in 10th grade, it all seems to cross over between the two.

Oh well, i guess all i really wanted to do was say hi and warn you guys that you may get a lot of simpleton questions sent your way to help with my homework. Just to let you know.
Thanks- Zack

posted in C++ - 6 replies

New to C++

2004-04-12T03:54:57Z

I know some basic programming... I can write Java and HTML easy. I been really interested in the language. I would like to say Hello to everyone I am a new member and also I have a question.

Where or how is the best way for me to learn C++? I have visual studio 6.0

posted in C++ - 1 reply

C++ implementations (virtual methods in constructor OK?)

2004-03-23T23:40:47Z

A couple years ago, a friend of mine who's a fellow C++ geek mentioned that virtual methods should not be invoked from a constructor because it's unknown whether a given C++ implementation initializes a class's virtual table before or after its constructor is invoked.

This isn't an issue with the C++ version I've worked with (Microsoft's Visual Studio C++) but I'm wondering whether anyone here has run into an implementation where it IS an issue. I haven't checked g++ yet...

Best, Don

posted in C++ - 4 replies

Homework Help!

2004-03-23T22:54:45Z

Alright, i told y'all you'd be helpin me soon

heres my first problem:
Why is this function telling me that i'm not using an array?
i passed it an array with the x and y floats but i keep geting the error, or should they not be floats?

float segmentLength(float, float, float, float);
float polygonPerimeter (float x, float y, int pnts)
{
float d;
int i;
for (i=0; i<pnts; i++);

d = segmentLength (x[i], x[i+1], y[i], y[i+1]);

return 0;

posted in C++ - 6 replies

Mastering C++

2004-03-17T14:44:58Z

I don't know if I ever will master C++. I've been working in it for going on 7 years, and I'm still frightening myself with new constructs.

Take templates for example. First I just used them, and they worked. (cool) Then I created abstract templates and inherited from them and that worked (frightening). Then today, I was staring at two simple templates in one of my utility include files. One was for singly linked lists, and the other for doubly linked lists; and I said to myself, these share a lot of common traits, I wonder if I could have a template that is built from another templatized class. So I tried something like this:

template <class T> class listbase { ... } ;
template <class T> class singlelist : public listbase<T> { ... } ;
template <class T> class doublelist : public listbase<T> { ... } ;

and it worked.
and then I put in an internal class for iteration, but made a second version that returned a different type:

template <class T> class listbase {
template <class Tpar> class Titerator {
iterator(T *) ;

Tpar * getcurrent(void) const ;
...
} ;
...
} ;

And of course I used it from the child class:

class myclass : public somebase {
singlelist<myclass>::Titerator<somebase> ...
} ;

And this all works.

Worse, is I know I'm not even scratching the surface. I've looked at the source code for the cross platform libraries from ObjectSpace (written by the guys that wrote the STL), and my mind bends just trying to follow what they're doing (generic algorithms, etc.)

Anyways, if anyone wants to look at my list templates, let me know and I'll email you a copy (about 200 lines); and if anyone has other good references for mind expanding C++ stuff, please post it here or let me know.

Derek

posted in C++ - 3 replies

Improving the language.

2004-02-28T05:53:16Z

So besides the obvious fixing of *p++ to not be horribly expensive, I was thinking today about invariant objects (borrowed technique from java).

Usually I have something like:

class simpledata {
public:
simpledata(int v1, int v2) : m_v1(v1), m_v2(v2) { }

const int m_v1, m_v2 ;
} ;

This way I can let others see m_v1 & m_v2 and not worry about the values getting modified. Unfortunately it doesn't work with char[].

class simplestringdata {
public:
simplestringdata(int v1, char * s1) : m_v1(v1)
{
strcpy(m_s1, s1) ; // XX - not allowed
}

const int m_v1 ;
const char * const m_s1[MAXSIZE] ;
} ;

My solution is let const members be modified in the constructor. It seems the right thing to do, after all you can do it in the initialization list, why not the constructor. Maybe special case it to only allow it for const int members at the same level, ie you can't modify const members of your parent. (Or maybe you could ...)

And no, the answer is not to use the 'string' class.

posted in C++ - 0 replies

silly pointer question

2004-02-19T18:34:01Z

What's this do? I assume it crashes the app, if not the whole system, but knowing very little about memory architecture I could see it doing something weird like wipe my BIOS. So I'm afraid to compile it and find out. Oh, and tribe doesn't like my indents, sorry.

void main()
{
for (int x=0; 1; x++)
*x=0;
}

posted in C++ - 12 replies

Darn it! Shucks!

2004-02-14T19:35:18Z

News item: leaked Windows code contained profanities.
When I worked at Microsoft, there were indeed profanities in Windows NT code. However they were quickly removed once we created a searchable content index of the source code. The managers would play with the contex index by querying for all the standard cuss words. The funny thing is that they didn't realize we were logging all the queries. We would later go through the logs and chuckle at Dave Cutler's or Jim Allchin's queries. In a few weeks all the profanities disappeared.
So either Microsoft Systems turned off the content index or, more likely, the leakers added their own comments.

posted in C++ - 0 replies

Three Languages

2004-02-12T22:29:25Z

Surprisingly, I like the new programming model proposed by Microsoft for Longhorn.

The way I normally program interactive applications is by dividing my code into the trio: model, view, and controller. The view is responsible for displaying stuff; the controller, for processing user input; and the model, for the hard work.

In Longhorn (codename for next version of Windows), you'll be able to use three different languages for the three components.

The view in Longhorn is programmed a lot like a web page, using XAML (Extensible Application Markup Language) which is a lot like HTML. The simplest applications could be written entirely in XAML, just like most web pages are written in HTML. That's the view part.

If you want to add more interaction with the user, you have to add a controller. You do it, for instance, in C#. The interactive elements in your view will have C# handlers. This is again very similar to how interactive web pages are made--using some kind of scripting language, like JavaScript or VB.

Finally, if you want your application to do some heavy work, you'd write the model--and here you may choose yet another language, for instance C++ -- for robustness and performance.

I think it's a cool idea.

posted in C++ - 10 replies

windows graphics

2004-02-02T02:15:36Z

I'd love to get back into coding, but i get so bored if i don't have a project that i'm interested in, and that basically means games. Which pretty much means graphics, plus realtime keyboard input. But there's not all that much info out there that's helpful to someone new with the language; i don't even know which compiler i should use.
I should mention that i don't expect to start off doing 3d, particle systems, and all that... if i had the tools to make say, a tetris clone i'd be happy for now. So... any advice?

posted in C++ - 13 replies

C++ a dying art?

2004-01-21T06:16:54Z

Just an obervation,

The C++ tribe here is languishing in relative obscurity compared to the PHP, Python, and Java tribes here at Tribe.net. I love C++, although the syntax can get a bit dense at times, but I am wondering: Are we just holding on to a dinosaur or is it the makeup of the Tribe.net community that creates this dichotomy?

Any ideas?

posted in C++ - 11 replies

Future of C++

2004-01-09T23:24:58Z

Scott Meyers, Adrei Alexandrescu, and Herb Sutter are not only top C++ experts but also very entertaining people. A must see next time they come to a panel discussion near you. Andrei the scientist, Scott the wise guru, and Herb the enthusiast shared some interesting insights. They were all worried (and righlty so) about the increasing complexity of the language. C++ is so difficult to parse that there are virtually no programming tools that require the analysis of a program. For instance, there is no decent C++ browser (don't even get me started on the MS VC++ browser). Teaching C++ is a nightmare. And, worst of all, people are being caught programming by trial and error (until it compiles). I'm afraid this is the fate of any language that is being designed by committee (the standarization committee). At this point C++ plays a very important role of a testbed for new features that hopefully in some near future will be implemented correctly in a completely new language. For now, we have to program in the language that even compilers cannot understand.

Anyone disagreeing with me? I'd like to hear your thoughts.

posted in C++ - 7 replies

Needing help or an online source

2003-12-27T07:12:03Z

I wrote a console32 app on a PC a while back and I need to update it. Basically, it converts an .avi to a series of .bmp's and custom formats. Now I've got an .avi where the source asset is gone and it appears to be DivX (or MP42 which isn't really important). Since I'm able to play it the codec is obviously installed.

In the past I simply called AVIStreamOpenFromFile()and AVIStreamGetFrameOpen() which now returns an error. I've since tried a variety of functions including ICLocate() which tell me no decompressor is installed. Now I know it can be done but I also know it's not easy. Most commercial software cannot handle the file, Premiere, TMPeg, etc. But older Paint Shop Pro 6 can for some reason. So they are obviously doing something the others and I are not.

I also swear I decoded the same file 2 months ago, so either a change in the codec or a Windows Update media change broke it.

So, I know asking here is a long shot, but does anyone know an online resource for Windows coding crap like this?

Thanks,

Hypno-Toad
expecting nothing but the sound of crickets

posted in C++ - 5 replies

C++ has no equals in its domain

2003-12-02T00:00:38Z

So far there is no competition for C++ in it domain. But you have to realize what C++ domain is. It's not writing small applets or web pages. C++ is specifically designed to deal with large complex programming tasks. Its power is in being able to express high level concepts by allowing the creation of multi-level abstractions. First you abstract your concepts into functions, then into classes, patterns, templates, etc. In no other language can you have such powerful tools as those in the C++ Standard Library. The power of the Standard Library is the way it abstracts common concepts--for instance iteration over the contenst of various containers (including low-level arrays). Try abstracting the iteration or searching behavior in Basic, Java, or C#.
Bartosz

posted in C++ - 4 replies

SGI is having a contest....

2003-11-07T09:22:33Z

to make the best demo of Cg and HLSL tech for their ATI GL chipsets...

Grand Prizes
2 winners will each receive one Onyx4 UltimateVision system -- the most powerful visualization system on the planet -- approximate retail value $40,000 each.
First Prizes
5 winners will each receive one ATI FireGL X1-128 workstation graphics accelerator card, designed for professional engineering and digital content creation applications based on the OpenGL® API.

http://www.sgi.com/visualization/onyx4/challenge/overview.html

-MAS

posted in C++ - 1 reply

Tokamak Physics library

2003-10-14T08:10:43Z

This is a rad C/CPP physics lib being developed by the guys at tokamakphysics.com ...
It is free free free and has great collision detection, joints, rigid body dynamics.. ragdoll physics etc..
Checkitout if yer into that kinda thang...

posted in C++ - 2 replies

Online C++ Book

2003-10-08T03:31:03Z

It's not self-promotion, just an attempt to start sharing C++ resources. My book "C++ In Action, Industrial Strength Programming in C++" (Addison-Wesley) is available online at my company's web site. There is also a discussion forum and a bunch of Windows API tutorials. Enjoy!

posted in C++ - 1 reply