C :: Assign A Pointer To A Function?
Jan 24, 2013How can we assign a pointer to a function? const char* function_name(), here what exactly does the pointer point to?
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C++ :: Why Assign A Pointer To Array
Jan 15, 2015Why would you ever assign a pointer to an existing array?Take this link for example. URL....I understand that pointers use dynamic memory allocation so they are much more flexible then a built in array, but if you already have an existing array, don't you already have static memory allocation for that array? Why bother assigning a pointer? Regardless of the pointer, doesn't the program still allocate static memory to the array anyway?
View 3 Replies View RelatedC :: Assign Pointer Of A String To Integer
Mar 22, 2014I have this code:
Code:
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
[code]....
What I want is basically to assign to the *p the pointer of the string so that i could do the following printf(" print string %s",*p); so i dont know how to do that.
C :: Assign Strings To Double Pointer
May 2, 2013When I try to assign strings to a double pointer, it only prints out the last string when I try to print everything out, and then it segfaults.
Code:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
main(){
char **test = calloc(3,sizeof(char));
[Code] .....
Am I assigning something the wrong way? Also, I am trying to avoid using array notation in order to practice, at least for the assigning of the strings.
C :: How To Assign Values To Pointer Char Array
Aug 10, 2013I can assign values to pointer character array like this...
Code:
char *array[4]={"abc","xyz","dgf","sdt"} ;
but the case is i don't know how to assign strings through key board ???? with using gets ,getchar or other suitable function
C :: How To Assign Value From A Function To Variable
May 26, 2013Im starting with C. Like I said in the title, how do I assign the value from a function to a variable? I mean I have this function:
Code:
int EnteroAleatorio(){
rand();
return rand();
}
and I would like to assign the value of EnteroAleatorio to a variable in my main function, but when I try to do it and compile, I got the next error: non-lvalue in assignment
C++ :: Read Function - Compare And Assign Variables
Mar 1, 2013I am developing a program that will read a function (x^2+2x+4 or other function) and then comparing and start assigning variables. My idea is with an array:
int i,x;
char xs;
char function[20];
cin.getline(function, 20);
cout << "Your function is: ";
[Code] .....
Well this is my basically idea, but when the program detect an ^ this will be associate with the exp(x,n); well in general the user enter a function: x^3+3x^2+4x-8 give a value for x for example 3 and the program will convert in -- exp(3,3)+3*exp(3,2)+4*3-8 --, but I don't know how.
C :: Calling Function Via Function Pointer Inside Structure Pointer
Mar 14, 2013I'm trying to call a function via a function pointer, and this function pointer is inside a structure. The structure is being referenced via a structure pointer.
Code:
position = hash->(*funcHash)(idNmbr);
The function will return an int, which is what position is a type of. When I compile this code,
I get the error: error: expected identifier before ( token.
Is my syntax wrong? I'm not sure what would be throwing this error.
C/C++ :: Read From File / Assign As String And Call Function As Argument
Oct 29, 2014I try to use passing function as argument but I'm stuck. I have two questions: First, I try to call uppercase and open .txt in tfm Second, How can I read characters from in.txt as string and assign to char content[] ?
#include <stdio.h>
void tfm( char str_filename[], void(*pf_convertion)( char content[]));
void uppercase(char content[]); //converts all letters to uppercase
int main(){
puts("-------------------------------");
printf("tfm:
");
tfm("in.txt", uppercase);
[Code] ....
Visual C++ :: How To Assign Const Char Return Value Of A Function To Label In Windows Form
Sep 30, 2013I am a newbie to C++ and VS ++. I have created a windows form application by dragging and dropping button, label..etc. i wish label text to be appeared as return value from a function. The function returns ' const char* '.how this returned string pointer can be used to display label text.?
View 9 Replies View RelatedC++ :: Calling Defined Function Pointer From Another Pointer To Class Object?
Aug 19, 2014I am attempting to implement function pointers and I am having a bit of a problem.
See the code example below; what I want to be able to do is call a function pointer from another pointer.
I'll admit that I may not be explaining this 100% correct but I am trying to implement the code inside the main function below.
class MainObject;
class SecondaryObject;
class SecondaryObject {
public:
[Code]....
C/C++ :: How To Get Formation From Pointer Function To Main Function
Feb 13, 2014int example (int [], int, *int,*int,*int,*int);
int main () {
My code will be here
example (int array[], int size, &a,&b,&c,&d); // Like this??? I try it didnt work
[Code] ....
C :: Using Pointer With A Function
Mar 6, 2015I tried to use pointer with a function but I guess I am missing out on something
Code:
#include<stdio.h>
int add(int *a,int *b){
int *c,*d;
*c = *c+1;
*d = *d-1;
[Code] ....
And this one too
Code:
#include<stdio.h>
void add(int *a){
int *c;
c = c+1;
[Code] ....
C++ :: What Does Pointer Before Function Mean
Apr 1, 2014I was wondering what magic does a * pointer before function actually do? Today our programming teacher asked us to look into it and explain it in the next class!
#include<iostream>
using namespace std;
int *binary(int []);
[Code].....
C :: Dereference A Pointer In A Function
Feb 25, 2015Code:
void dereference(int* a, int* b)
{
a=b;
}
int main(int argc, char **argv)
[Code] ....
Why isn't f and d the same after calling "dereference(f,d);"
C :: Returning Pointer From Function
Nov 21, 2014As the title says, i'm using a function which returns a pointer to a struct:
the struct is the following:
Code:
typedef struct POINT
{
uint16_t x;
uint16_t y;
}
Coordinate; the function i'm using:
Code:
Coordinate * Read_XTP2046(void)
{static Coordinate screen;
//calculations to determine the coordinates
screen.x=(temp[1]+temp[2])/2;
screen.y=(temp[0]+temp[2])/2;
// and so on...
return &screen;}
The question is: how do i catch this pointer and make it into a Coordinate struct in which i can read the x and y.
In my main program i would do the following:
Code:
Coordinate cor;
cor = Read_XTP2046();
This does not work, as the function returns a pointer, but how to transform this pointer into a Coordinate struct.
C :: Initialization Of Function Pointer
Apr 28, 2013I would like to initialize an arry containing function pointers with adresses of functions that have a variable number of arguments.
Below the code that works in principle. I would however get rid of the warning message during compilation pointing to the initialzation of the funtion pointers in the array. How do I need to cast the pointers to the functions ?
Code:
gcc func_ptr_init.c
func_ptr_init.c:28: warning: initialization from incompatible pointer type
func_ptr_init.c:32: warning: initialization from incompatible pointer type
Code:
#include<stdio.h>
unsigned char func1_ptr(unsigned int* if_desc, int* result_code) {
*if_desc = 1;
*result_code = 1;
return(0);
[Code] ....
C++ :: How To Return A Pointer From Function
May 1, 2013I am trying to return a pointer from a method. Below is a sample of my code.
CSubnode * CTest::GetSubNode() {
return m_psubnode;//this is declared in CTest as CSunbnode * m_psubnode
}
//in another class
m_subnode = m_ptest->GetSubNode(); //m_subnode is declared as a pointer
Is this the correct why to return a pointer?
C++ :: Setting The Value Of A Pointer From Function
Feb 20, 2013I declared a pointer in main with value 0, so I want to change its value so that it points to other variable from a function, I guess the function creates a copy of my pointer that's why whatever I do within function doesn't change the real direction of the pointer in main. I've been trying something like this:
#include <stdio.h>
void redirectionate(char *str, char *ptrCopy);
int main()
{
[Code]....
C++ :: What Is The Actual Use Of Function Pointer
Dec 27, 2013two things I did'nt get till now
Q->1 what is the actual use of function pointer ?
Q->2 what is use of passing function as an argument to another function ?
C/C++ :: Pointer As Function Arguments
Dec 26, 2014How this code work bcoz when pointer variable assigned in called function and how different values get as resultant output, ans 2 97 for below code. How the code wil execute so that i can validate ans
#include <stdio.h>
int main() {
int i = 97, *p = &i;
foo(&i);
printf("%d ", *p);
[Code] ....
C++ :: Pointer To Member Function?
Jun 6, 2012I am trying to use "remove_if" with a predicate function inside a class. The code intends to remove the grid cells which an agent cannot move into (from among all possible cells).
Code:
void classname::function1()
{
vector<MoorePoint> neighbors;
....
[Code]....
That code would work if it was not in a class and the predicate was not a member function. However, now I receive long error messages which I guess refer to incompatibility of remove_if template with the predicate parameter (one error includes : error C2064: term does not evaluate to a function taking 1 arguments).
C++ :: How To Properly Use Pointer To A Particular Function
Apr 4, 2013#include <iostream>
using namespace std;
int function(int a,int b) {
return a + b;
} bool function2(int a,int b)
[Code] .....
C++ :: Pass Object As A Pointer In Function
Apr 12, 2013i need to pass myboard.board (board is in the class Cboard and it is an array of int) to a function in a class called piece however this is troubling . i need to pass it as pointer os that i could change its value here under is my code.
main.cpp Code: #include<iostream>
#include"board.h"
#include "pieces.h"
[Code].....
C++ :: How To Call A Thread By A Function Pointer
Nov 24, 2014How to call a thread by a function pointer?
I get "error C2059: syntax error : '(' " on the indicated line.
Code:
#include <windows.h>#include <iostream>
using namespace std;
DWORD WINAPI Thread() {
cout << "ok" << endl;
return 0;
[Code] ....
C :: Passing Structure Pointer To A Function
Aug 24, 2014I am trying to wright a program that takes student grade data from a command line file, calculates a final grade, and copies the final grades to an output file. So far I have two functions, one that creates a student structure by allocating memory for it and returning its address, and one that should take that address and fill it with data from a line from the input file. My ultimate goal is to use a linked list to connect all the structs, but for now I just want to get the functions working. When I run what I have so far, I get an error C2440 (using visual 2010) that says "cannot convert from 'cStudent *', to 'cStudent', and points to the line where I call my fill function. How should structure pointers be passed?
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct student // Declaring student structure globally.
[Code] .....
Also, here is a sample of what a line from the input file would look like:
Bill Gates, 60, 54, 38, 62, 65, 60, 50