I have a void that needs to end a program but a break and return 0 both won't work. Instead I have it cout (1/0). It works but is there an alternative?
#include <iostream>
#include <thread>
#include <Windows.h>
#include <limits>
using namespace std;
double clicks=0;
double result;
bool gameon=false;
[Code] .....
As part of my ongoing c programming education, I have written a program to use void pointers in a function,
Code:
#include <stdio.h>
#define MAX_NUMBERS 10
size_t size(void *object);
int main(void) {
}
[code]....
Now I think that the result 4 is the size of the pointer, so I'm confussed as why it doesn't give me the same result as 40.
The error is coming up in line 13(srand() issue I think) of the following code:
#include <cstdlib>
#include <iostream>
#include <cmath>
#include <ctime>
using namespace std;
int main(int argc, char *argv[]){
[Code] ....
I'm sure it's something really simple that I'm overlooking.
Using a template in the assignment, I don't know what I did wrong?
Code:
#include <iostream>
#include <string>
using namespace std;
template<class T>
void mpgcalc(T& Miles, T& Gallons)
[Code] .....
how can i use the void pointers? i understand that can recive an adress variable(&). but can recive a value?
Code:
int a=5;
void *d;
b=&a;
b=100;//???
why i can't do these?
Why is it not okay to return void? Most compilers will probably let you (gcc does) but it gives you a warning that you aren't supposed to. Most languages allow you to return void.
Something like
Code:
void log(const std::string & txt){ std::cout << txt << std::endl; }
//C++ way to do it
void bar(int i){
[Code].....
I am trying to add data to a queue with the following simplified code:
Code:
typedef struct Queue {
void * data;
int head;
int tail;
int elementSize;
My question is, how do I move the queue->data pointer to the correct memory location in order to copy given data to head? The code above inside memcpy gives med the error: "expression must be a pointer to a complete object type".
Do I need an extra pointer to be able to navigate between the queue's head and tail, and keep queue->data as a reference to the first byte of the allocated memory, or is it possible with only queue->data?
Edit. Just noticed I have mixed up head and tail. The enqueued data should probably go to the Queue's tail and not the head. However, the problem is still the same.
I could understand void pointers I created the following program:
Code:
#include <stdio.h>
#include <string.h>
int main(void) {
char word[] = "Zero";
int number = 0;
void *ptr = NULL;
[Code] .....
The program works fine, however i really want to fully understand what is going on with the dereferencing of the void pointer, for example: With the following code:
Code:
ptr = &number;
*((int *)ptr) = 1;
Why can't you just do:
Code:
ptr = &number;
*(int *)ptr = 1;
And again with this code, (i'm guessing it's becuase its a pointer to a pointer?):
Code:
ptr = &word;
strcpy(ptr,"One");
If i declare a function as a void function. But for testing purpose if i use a return statement in the function definition. i have tested and found that the function does not return and executes the entire function. How does the function not return even if a return statement is available? Does the compiler removes this return statement or how it is?
View 2 Replies View RelatedCode:
int main() {
List* newList= lst_new();
names* nama;
char* data;
int x=1;
[Code] ....
I cant seem to be able to print a string.. the functions lst_next() lst_first() return void*.
Write a C++ program consisting of main plus two other functions which will do the following:
Take an integer input from the keyboard.
Send the integer to a function which will output the integer to the screen.
Send the integer to a second function which will tell the user that the integer is an odd value.
Do not tell the user anything if the integer is an even value.
Repeat this process until the user enters something which is not an integer; use input validation to check for validity.
Any not valid input should terminate the program.
I was reading about void as function argument, but I did not fully understand it's meaning in C.
In C++
void foo(void) {}
and
void foo() {}
are the same. It means no arguments for foo function. But in C it's different. First function means the same as in C++, but second means
In C, an empty parameter list means that the number and type of the function arguments are unknown. But if it is unknown you can't use this arguments if user specifies same. Because here are no variables to store them. So doesn't result are the some? You do not get any arguments. O do I can get this arguments from some hidden variable?
For example.
void foo() {
printf("%d", var);
}
foo(5);
It is very unclear for me. Do this apply to main function too?
int main(void)
int main()
or can I use arguments given to int main() like given to int main(int argc, char* argv[])
My assignment is to write a program using VOID FUNCTIONS WITH AN ARGUMENT.
*I need one non-void function with an argument to generate the first 15 numbers greater than 500, another non-void function with an argument to generate the first 15 perfect squares that are greater than 500. Last, they need to be in columns next to each other.* also i cant use x,y, coordinates to align them. i must create a for loop with the
These are some notes from examples in the class. i just don't know how to do it with non void functions with an argument.
#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
void ClearTheScreen();
void NormalTermination();
[Code] ....
I want to have a function that has a pointer to an int/double/string so I thought I'd use a void pointer like so:
int someFnc(int a, int b, const void *key){
// take care of converting key into appropriate type in here
}
And when I want to use this function I'd like to be able to do something like this:
main{
...
int myKey;
someFnc(1,2,myKey);
]
But I get a compiler error telling me:
invalid conversion from 'int' to 'const void' -[fpermissive]
Do I need to convert myKey into a void pointer before passing it as an argument?
Why does passing myKey like this work?
someFnc(1,2,&myKey);
How to declare variable for all void() as I have another void s in my C++ program. I want to have a variable that can use for all the void and not only in a simple void.Is it possible?
View 17 Replies View Relatedint (*cInts)(void*,void*);
cInts= &compareInts;
int x=(cInts)(2,5); //This wont work. I tried a bunch of other things
printf(x);
I need this break in my main function, but I'm not allowed to put it in void since void is not located in a loop. How can I solve this?
Code:
#include <iostream>#include <string>
using namespace std;
void login(string x, string y);
string username;
string password;
string x;
string y;
[Code] ....
I wanted to make a multiplication table.
Here's the code:
#include<iostream>
#include<conio.h>
using namespace std;
void initArray(int arg1[50][50], int r, int c) {
int val=1;
for(int row=0; row<r; row++) {
[code]....
I want the output to be like this:
1 2 3
2 4 6
3 6 9
If the user inputs 3 rows and 3 columns.
I keep getting an error "Invalid use of void expression" on line 12.
Code:
#include<stdio.h>
#include<stdlib.h>
void initialiaze_array( int size );
void print_array( int size );
void replace( int num, int i );
[Code] ....
void(..)
bool(..)
Direct to the board[8][8].
I've been trying to get my program to call void functions with an if statement, but when i run my program and try to call one of the functions "worst case, best case, or random case" it doesn't get called. It just prompts the original menu.
#include<iostream>
#include<fstream>
using namespace std;
void bubbleSort();
void selectionSort();
[Code] .....
I am making an app thing and basically what it should be doing is creating 12 different variables (about) and outputting one var/another var. but whenever i tell it to do this, it comes out with some random number. like this:
//starting with main.cpp, all of the .h's in the project don't have a corresponding .cpp
#include <iostream>
#include "Choosing Race.h"
#include "Choosing Class.h"
#include "HuF.h"
[Code] ....
This outputs this:
list of races:
1.) Human
what is your race?: 1
list of classes:
1.) Fighter
what is your class (type n for next 10)?: 1
what is your level?: 40
Build your enemy: List of races:
1.) Human
what is your enemies race?: 1
list of classes:
1.) Fighter
what is your enemies class (type n for next 10)?: 1
what is your enemies level?: 40
(lldb)
lldb is basically it saying theres a mathematical issue somewhere. the problem is in the void FightStart() function. its dividing by a 0 when it shouldn't be. what should i do to get this to work.
The purpose of this code is to calculate a pagecheck for intered hours and overtime for any hours over 40! This is what I have so far!
#include<iostream>
using namespace std;
void Amount (int hours, int wage, int sum);
void printCheck(int sum);
int main()
[code]....
I want to know how to dereference a void pointer through the way of typing it.
Lets just say that I malloc'd a huge bunch of memory and i can do whatever i want
void* randomData = malloc ( 1000000 );
And i decide to make my own virtual 'int'
I am not sure how to do this.
*( int* ) ( randomData + 10 ) = ( int ) 323453 //323453 can be an int variable aswell
Im not sure if this is the right way to do perform a dereference.
This is an overview of what has to be done:
-The pointer has to be dereferenced
-Cast the pointer as an int pointer so we can change it like a normal 4-byte int
-Perform pointer arithmetic, so that the int can be placed anywhere we want
I want to write a code that gets three values from the user and puts them into three arrays. When the user enters -999, I want to print out a chart showing all the values they put in. This is what I have so far but it wont build. It tells me std::string is requested, but I'm not sure where to put it, and printArrays is declared void. How can I fix this?
#include <iostream>
#include <string>
using namespace std;
const int ARSIZE = 400;
void printArrays (string reportTitle, int levelsArray[], int scoresArray[], int starsArray[], int i);
[Code] ....
how do you open a file inside of a void function
this is the code i have
#include <iostream>
#include <fstream>
#include <sstream>
[Code]....