Programming :: Use A Class Inside A Struct?
Apr 8, 2011Is is possible to use a class inside a struct? I keep getting segmentation fault with this code:
Code:
struct my_struct {
unsigned count;
std::string msg;
[code]....
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Programming :: Declaring A Vector Inside A C++ Class?
Mar 23, 2010Is it not possible to declare a vector inside a C++ class ? Have a look at the following code:
Code:
#include <stdio.h>
#include <iostream>
#include <malloc.h> // malloc
#include <strings.h> // bzero
[code]....
Programming :: STL Container Into A C Struct
May 23, 2011I have an old C application in which i am trying to include some STL cointainers. When i use the STL container alone it works fine, but when i include it into a C struct i have segmentation faults errors. I know that it is not a good idea to mix C and C++. Considering this code:
Code:
typedef struct{
int shmid;
...
APPLSPACETYPE applSpace;
[code]...
and how to make a malloc for this issue; something like :
Code:
mem->applSpace.rData.completeGroups2zeroGroup=(map_completeGroups2zeroGroup_type *)malloc((sizeof(map_completeGroups2zeroGroup_type)+1)* sizeof(char ));
Programming :: Difference Between Struct And Union?
Nov 6, 2010I have been spending time (starting yesterday) reverse-engineering GTK+ to get my programming skills up. I came across a struct in the headers (_GtkArg, which was then typedeffed into GtkArg) that includes a union in it that has pretty much the same properties as a struct. Then, there was a struct inside the union.
I'm confused. Just what is the difference between a union and a struct?
P.S. I am using GTK's native C programming language.
Programming :: Memory Allocation For Struct In C++?
Mar 30, 2010How do we allocate memory of struct? what i did was
Code:
int main()
struct amp
{
[code].....
cout <<"The size of 'struct' is"<< sizeof(struct amp)<<"and it is located at"<<struct amp*s = malloc(sizeof(struct amp))<<endl;
it gives me an error---
In funtion 'int main()':
error: expected primary-expression before 'struct'
error: expected ';' before 'struct'
Programming :: Python Serial And Struct On 64 Bit?
May 14, 2010For a work project, I've got a bunch of python code from about a year ago that controls the movement of our EVI-D30 camera over a ttyUSB connection. It used to work fine on a 32-bit Fedora box, but recently we moved our whole project over to a 64-bit Gentoo server, and the same code seems to be worthless on the new platform. I didn't write the code, so I'm have trouble figuring out how to fix it. Error messages usually look like this:
Code:
File "./CameraController.py", line 172, in pan
turn_callback(cmdStruct[0], cmdStruct[1])
File "./CameraController.py", line 147, in turn_callback
cameras[camera].TiltUp()
[code]....
Programming :: Stl Vector As A Member Of A Struct?
Jan 17, 2011is there any problem that might rise by by having a vector as a member of struct in c++ as follows.ex.
struct A
{
int a;
[code]...
Programming :: Access Value From Nested Struct <c Language>?
Mar 11, 2010I having a nested structures which are referenced with pointer variables :
example :
typedef struct {
int a ;
char *b ;
int *c ;
}EXP2 ;
[Code]...
While trying to access the value of sv.exp2->a it throws segmentation fault error.How to acess this variable ??
Programming :: Sizeof Struct With Function Pointers As A Member?
Jul 2, 2010I following structure
typedef struct
{
[code]...
Programming :: Dereferencing Pointer To A Shared Memory Struct?
Feb 5, 2011I have what should be a relatively simple program (fadec.c) that maps a struct from an included header file (fadec.h) to a shared memory region, but Im struggling accessing members in the struct from the pointer returned by shmat. Ultimately, I want to access members in the shared memory structure with a globally declared version of the struct, shm__. Not only do I not know how to accomplish that, but I cant even seem to access members of the shared struct directly from the pointer itself (compiler complains about dereferencing pointer to incomplete type). Im at a loss and could use another set of eyes if you guys dont mind taking a gander:
Compile Errors:
tony-pc:/cygdrive/p/test> cc -o fadec fadec.c
fadec.c: In function 'main':
fadec.c:30: error: dereferencing pointer to incomplete type
fadec.c:31: error: dereferencing pointer to incomplete type
[Code]...
Programming :: Struct Timeval Doesn't Keep After Function Returns
Jun 2, 2010int GetTime(struct timeval tv)
{
gettimeofday(&tv, NULL)
printf("%d
", tv.tv_sec); /* here is the right value */
return 0;
}
[Code]....
What happend? struct timeval has a self timer?
Programming :: Create A Global Struct Variable With Predefined Member Values?
May 26, 2010Is it possible to create a global struct variable with predefined member values?Only one instance of that struct is ever needed.
View 1 Replies View RelatedProgramming :: Differences Between Ncurses Library And Termios Struct W.r.t Keyboard Reading
May 3, 2010I want to read a pressed key or a combination of pressed keys from the keyboard and perform some action afterwords.
e.g.
Ctrl-Alt-F1
Out of ncurses lib. and the termios struct which can be used best for the above purpose and why ?I tried to search on Google, the differences between these two but couldn't get much !
Programming :: Kernel API *get_super (struct Block_device *bdev) Producing Error With Fedora Core 5
Feb 2, 2011I understand that block_device pointer *bd sholuld get initialized. Program should produce initialization error for *bd. Compiler is producing '->'. I am not understanding why?
[code]...
Programming :: Kernel Module - Task_struct / Files Struct, Open_fds, And The Open File Descriptors In Task?
May 1, 2010This for Kernel 2.6.29.6. I'm trying to code a kernel module that displays process information.
how to count opened file descriptors per task. I have been able to write a module that lists all the current process names along with their pid number in /var/log/messages. Basically, I cycle through the ring of processes using the macro for_each_process(task) and printk the comm and pid of each task. I'm trying to see how many file descriptors each task has open. I've been reading up in books and all over the internet. At first I thought I needed to access max_fds under files_struct, but that just lists the maximum number of file descriptors that can be opened per task, which by default is set at 256. I then thought about counting the elements in the fd_array. But then I learned that every task's fd_array is initially set at 32. Now I know that I need to access open_fds of type fd_set * in files_struct. open_fds is a pointer to all the open file descriptors. The problem is that I don't know how to access a pointer of type fd_set.
Is there a good guide or book that really focuses on type fd_set and open_fds? Every book and resource I've read never really go into depth on this. relationship between files struct, open_fds, and the open file descriptors in task?
Programming :: Build A Simple Program For C Programming Class?
Feb 12, 2011im trying to build a simple program for my C programming class, this is the source code
#include <stdio.h>
int main()
{
int length, width, length, height, area, perimeter;
perimeter = width + length + height;
area = width * length + heigth;
[Code]...
i dont see any error (you might)but every time i run it it runs but after it asks me to input for the width i do it but it doesn't take me to the length, it just stays blank until i input another value in the same place for the width, it asks me for 4 inputs in total i don;t know why, and after i run it different times it gives me different values for the perimeter and are. how can I fix this?
OpenSUSE Install :: Cannot Compile Vdrift-2009-06-15 - Warning: The Options Class Is Deprecated; Use The Variables Class Instead
Mar 12, 2010I have a problem with compiling vdrift-2009-06-15 using scons. As the source that i obtained only supports scons i cannot use make. the error that i get when i try to compile it in GNOME Terminal is: scons: Reading SConscript files ... scons: warning: The Options class is deprecated; use the Variables class instead.
File "/home/mohit/Download/vdrift-2009-06-15/SConstruct", line 9, in <module>
scons: warning: The BoolOption() function is deprecated; use the BoolVariable() function instead.
File "/home/mohit/Download/vdrift-2009-06-15/SConstruct", line 13, in <module>
Checking for C++ header file asio.hpp... (cached) yes
Checking for C++ header file boost/bind.hpp... (cached) yes
Checking for C++ header file GL/gl.h... (cached) yes
Checking for C++ header file GL/glu.h... (cached) yes
Checking for C++ header file SDL/SDL.h... (cached) yes
[Code]........
Programming :: Passing Class To Itself (CPP)?
May 18, 2010I'm struggling with the issue of passing a vector of a class to itself, here's what state its in now... (tried many variations, but without direction).
Code:
#include <iostream>
#include <string>
[code]...
Programming :: C++: Defining A New Class - Periodic B.c?
Apr 9, 2010I am trying to make a periodic boundary condition type function, using an existing class given to me in lecture notes, but am having some trouble! Effectively, I am trying to make an array such that, for a point in any row of a 2D matrix ("Matrix(i,j)"), the command "next_i[i]" will return "(i+1)%L", where L is the number of data points in the row. This will enable me to select a point to the right of any point in the matrix: "Matrix(next[i],j)"
[Code]....
Programming :: Unable To Compile Class For JSP?
Mar 15, 2011My new guy has created several functioning webpages on his machine with TOMCAT 6 with Sun JDK, yet our machines use TOMCAT 5.5 with Open JDK, which his webpages don't show. Do you have any idea how to make them work? The error showing in a browser:
Code:
HTTP Status 500 -
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception org.apache.jasper.JasperException: Unable to compile class for JSP:
[Code]...
Programming :: How To Set Up Global Class In JAVA?
May 10, 2011I've had to do some code in java, a language I'm very much unfamiliarly with so please excuse my incorrect use of terms. The basic outline of my problem is I create a class object as a local within a swing button function it works fine. If I create it as a global ( with I think I need to do ) within main, then prototype it with the other swing objects at the bottom of the file when it is called it causes a host of problems. I think the easiest way is to show it.
View 2 Replies View RelatedProgramming :: How To Modify ArrayList From Outside Of Class?
Mar 10, 2010Okay so I'm working on a program here as I'm learning java,I have an array that is initialized with 5 objects that are hard coded. I have made a GUI that takes the input needed and creates an object with those values.I need to add that object to the ArrayList that I have previously made.Okay, so I have three classes, guiclass.java, main.java and gladiator.java Objects are made and defined in "gladiator".Main contains my public static void main section, launches my gui, creates my five hard coded objects, creates my ArrayList and adds my five hard coded objects to the ArrayList.Now, I need to add the object that I generated in the guiSection [action Listener]to the ArrayList that I created in my main class's public static void main string... section. Problem is my arraylist "cannot be resolved" from guiclass.
View 13 Replies View RelatedProgramming :: Md5 In Java Without Using MessageDigest Class
Sep 18, 2010I am looking to write a function to return an MD5 hash in Java but I don't want to us the MessageDigest class as I am using the J2ME framework which doesn't include it.
View 3 Replies View RelatedProgramming :: Php And Variable Class Names?
Sep 30, 2010How can I handle the situation below so that the "Fatal Error" message is not shown. It would be ideal if I could supply a default class to be used. I'd prefer to not use: ini_set() to supress the errors but actually be able to "handle" the error.
Code:
<?php
class MyClass
[code]....
Programming :: Possible To Communicate Values Between Class?
Feb 24, 2009I have a application in C++, and now I have two class. MyDialog is the class that main function launch. In MyDialog class there are four elements and when I click over theese elements, there is a MousePressEvent that launch other class, Touchpad class. So, in some moments, I have loaded two class. My question is, how can pass a value from Touchpad class to MyDialog class, when I close (destroy) Touchpad class. In a few words, is it possible to communicate values between class?
View 5 Replies View RelatedProgramming :: Implement A Set Class (like In Stl) Using A Vector?
Sep 3, 2010i need to implement a Set class(like in stl) using a vector.Here is my code that doesnt work corectly:
Code:
#include <iostream>
#include <vector>
template<class T>
class Set
{
[Code]....
Programming :: Implement C_str() For A String Class?
Oct 19, 2010How can I implement c_str() for a string class?
View 2 Replies View RelatedProgramming :: Default Port For UDPWriter Class?
May 9, 2011This is a really specific question, but maybe someone can help. I'm debugging someone else's code, and they call a UDPWriter and specify an IP address and port, and I'm trying to make sure this multicast traffic goes over a certain port. How can I determine which port the UDP defaults to and change it?
It's confusing to me because I'm not familiar with all the layers the OS sends traffic through before it goes through the interface. Is there maybe some simpler way to tell the OS to send multicast traffic over both interfaces?
Programming :: Function Pointers To Class Members Cpp
May 23, 2010i'm a bit stuck playing with the following class setup for glut. The actual issue is with the function pointers.Basically the following code is the opengl redbook cube example slightly modified.
View 2 Replies View RelatedProgramming :: Getting Undefined Reference To Main In Sub-class For BST?
Apr 27, 2011I'm writing a binary search tree class to insert records and I'm stuck on the following error:
Code:
/usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../lib64/crt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
collect2: ld returned 1 exit status
Here is the code for my class:
[Code]...
I really don't know how to approach this, I thought that everything was working fine but I have no idea what is wrong. Also, for clarification, main() is in a different .cpp file that #includes "tree.h"