I am doing a piece of gui code on some embedded system.
I'm trying to find a way of eliminating the local variable kEvent:
Code:
EVENT kEvent;
....
Code:
kEvent = EVENT_UPSTREAM;
xStatus = xQueueSendToBack(getEventProcessorQueue(),&kEvent, 0 );
....
I tried this, it doesn't work:
Code:
xStatus = xQueueSendToBack(getEventProcessorQueue(),(EVENT *)EVENT_UPSTREAM, 0 );
Shouldn't this work?
I know that this code is wrong because it returns the address of local variable which no longer exist after function:
int *f1()
{
int x = 2;
return &x;
}
However, why this one does not show problem and runs fine, here the pointer p is also a local variable:
int *f2()
{
int x = 2;
int *p;
p = &x;
return p;
}
Can I return a non-dynamic local address of a var from a function?
int* func(int m){
m=1;
return m;
}
My compiler giving warning but compiles and returns add but My tutor handout says it will not compile...!!! she used array in func and returned arr[m]
I need to transform a local variable into a global variable so I can use it in one of my functions. I thought about passing the value as a parameter to this function but I can do this since the function is called inside the while loop and this variable counts how many times the while loop does (so the final value is outside the loop). Example to visualize better:
Code:
while(condition) {
function(parameter1, parameter2);
count = count + 1;
}
printf("%d
", count);
So, I need to transform the final value of "count" into a global variable. Can I do this?
#include <iostream>
using namespace std;
void myfunc(int* ); // what do i put in these parameters to accept a mem loc of a pointer
int main () {
int x = 5;
[Code] .....
SOLUTION:
#include <iostream>
using namespace std;
//Purpose to create a function that returns a pointer to a pointer
int** myfunc(int**);
int main () {
int x = 5;
[Code] ....
#include <iostream>
using namespace std;
struct node
{
[Code]....
How is this not working? just the add & display function.
Why do we not pass the address of the string during printf or scanf functions like we do for Integer or float variable types?
View 2 Replies View Related#include<iostream>
#include<stdlib.h>
using namespace std;
int Name(),Minimum(),Maximum();
int main() {
int name=Name(),minimum= Minimum(),maximum= Maximum();
[Code] ...
There are error to let user to key in minimum and maximum values, i would like to know whats the problem?
Should i never return a pointer to a local variable. i have seen the following code in the standard text book.
Code:
struct node *add_to_list(struct node *list, int n)
{
struct node *new_node;
new_node = malloc(sizeof(struct node));
// some code here
return new_node;
}
new_node is a local pointer then why is he returning the new_node? Is it wrong or am i failing to understand something?
Here is my overloaded operator :
const double & Waz::operator()(int i,int j) const {
return ((WazImpl const)(*p))(i,j);
}
Where in Waz class I have : WazImpl* p; and in the class WazImpl I have an operator () const
The warning is : Warning C4172 returning address of local variable or temporary
As far as I understand I'm returning a temp variable which is destroyed somewhere else what can I do to fix it?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Furniture {
class Program {
static void Main(string[] args)
[Code] ....
I tried changing the type of variable to char but i still get the same result. i also tried using a switch statement which was my first choice but i had the same issue.
I keep getting the "Uninitialized Local Variable" error. But for my code it's says it's the variable 'pay' in my Manager Function. This is the only error that is popping up.
I've tried setting pay to 0 but when I do, I get a bunch of external errors. I've also tried assigning pay to WeeklySalary like this:
double pay = WeeklySalary;
//Calculating pay for a company
#include <iostream>
#include <iomanip>
using namespace std;
//Function prototypes
double managerFunction();
double hourlyWorkerFunction();
double commissionWorkerFunction();
[Code] .....
{
//Declare Variables
decimal hrsWrkd, otPay, grossPay, taxRate=0, taxAmount, netPay,basePay, wage;
string maritalStatus;
const decimal WORKWEEK = 40;
const decimal OTRATE = 1.5m;
const double m = 0.15;
[Code] ....
The error message I am getting is Use of unassigned local variable 'otPay' . I see its been declared and been used in the code so the error is confusing, also when i run the program i noticed that it doesn't take out the taxes.
So I have been working my way through this assignment and I'm just stuck now. I cannot get this work properly It just tells me I'm trying to return a local variable when attempting to return postfix in the to_postfix function. It is line 97 that wont compile. Also I cannot change anything in runner.c.
Calculator.c
Code:
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <ctype.h>
4 #include <string.h>
5 #include "stack.h"
[Code] .....
I got the following lines of code from a book. The variable char c is being used here to demonstration local variable declaration.
while(char c = cin.get() != 'q') {
cout << c << " wasn't it" << endl;
if(char x = c == 'a' || c == 'b')
cout << "You typed a or b" << endl;
else
cout << "You typed " << x << endl;
}
It compiles and runs. There are two issues when I try to run it.
1) It seems to loop through two times for every entry. If I insert cin.ignore() just before the closing bracket, it seems to work better.
2) the variable c does not seem to have the character I entered when examined in the if statement.
What is happening with the variable c inside the while loop scope?
Does c actually get initialized?
#include <iostream.h>
#include <conio.h>
int main() {
int a;
cout<< "ingrese un numero entre 1 y 4 gracias
";
cin>> a;
switch(a)
[code].....
is it possible to have a global variable pointing to a different address depending on the thread?
Imagine one would like to use threads with the loop:
for (i=0;i<n;i++){
globalPointerVariable=getAddress(i);
DoThingsUsingThe_globalPointerVariable();
}
Here is the code,
Code:
class A {
};
A& CreateObject() {
static A a;
return a;
} static A aa;
int main() {
return 0;
}
So is there any difference between a defined in CreateObject and aa?
I've been experimenting with pointers and am getting the below error.
'error: cannot convert 'int**' to 'int*' in assignment'
I thought it was ok to assign a variable address to another variable. Line 18 is where I get the error.
I am trying to show the progression of memory as I increment it as I have done on line 17 and again, I don't know why I don't see a progression through memory locations when output to the console on line 20.
Here's the code:
#include <iostream>
#include <cstring>
#include <cstdlib>
using namespace std;
int main() {
int *tt = new int;
int *p = new int;
[Code] .....
i always get error case bypasses initialization of a local variable
here's my coding
my header files
Code: #include <stdio.h>
#include <conio.h>
#include <iostream.h>
#include <fstream.h>
[Code].....
i'm using borland c++ v5.02
When a declare a string e.g.
Code:
char str[30]; as a global variable, the srting is initialized to NULL.
But if I declare char str1[30] INSIDE main(), then the string has garbage inside.... Why this happens??
E.g. the following code snippet...
Code:
#include <stdio.h>
char str[50];
int main(){
char str1[50];
[Code] ....
i have highlighted the errors in block letters.
#include<fstream.h>
#include<conio.h>
#include<string.h>
#include<stdio.h>
#include<stdlib.h>
void login();
struct date {
int dd,mm,yy;
[code].....
Can local variable be passed as the parameter for a new created thread procedure? Here is the example code:
Code:
void CDLG::some_function()
{
CString strFileName="abc.doc";
//local variable, can it be valid for being passed into the following new thread???
//Can strFileName still be accessed from within the stack of thread procedure?
::AfxBeginThread(ProcessContentThread,(LPVOID)&strFileName);
}
[Code]...
There is another method using variable on the heap,
Code:
void CDLG::some_function()
{
CString strFileName="abc.doc";
CString* pstrFN=new CString(strFileName);
::AfxBeginThread(ProcessContentThread,(LPVOID)pstrFN);
}
[Code]...
I test these code, both methods work as expected, but I doubt whether the first method is a good way. OR if only the second method is the correct way to pass a parameter to a thread.
My address book will be simple, and the thing's that I'm expecting to use in it are :
Pointers, Linked Lists
Malloc
Structs
Typedefs
Makefile, header file
Putting functions into different program files
I have started the program trying to create a struct, and getting it working with a couple of entries before going onto user input and splitting it up.
Code:
#include <stdio.h>
#include <stdlib.h>
int main(void) {
// Struct type address book. Just a name, a number and a pointer
[Code] .....
I'm a bit lost at this point... My knee jerk thought is to create a for loop, and cycle through the list.
I'm not sure how this would apply to this though? Without using the familiar type of print loop such as :
Code:
for (i = 0; ;i++) {
printf("%i
", array[i];
}
I'm thinking that I need to create a temporary struct that can be used to assign the value of the next struct in the list, and then somehow print from that....
I'll try and write the logic out :
while temp != NULL (The last node value is assigned NULL to show us where the end of the list is)
create a temporary pointer that can be used to keep track of where we are in the list.
print out the current entry name and number
then assign the temp pointer value to the * next of the current struct. So if we are in entry1 the *next should be the address of entry 2.
Print out entry 2 name and number, assign entry 2 next to the temp value.
In Visual Studios I keep getting this error. cpp(36): error C4700: uninitialized local variable 'Eligible' used
Code:
#include <iostream>
#include <string>
#include <iomanip>
#include <fstream>
#include <cmath>
using namespace std;
void Getinput(int& Loantype, double& Income, double& Totaldebt, double& Loanamount);
[Code] ....
Consider the below initialization of x.
int x = 0x01234567;
If x is stored in RAM as given below, what would be the address x in both case?
(if image is invisible please follow this link)
Assume that size of integer is 4 byte.