C++ :: Multiple Files Causes (Multiple Definition) Error?
Jul 15, 2013
I'm using multiple C++ files in one project for the first time. Both have need to include a protected (#ifndef) header file. However, when I do that, I get a multiple definition error.
From what I found from research, adding the word inline before the function fixes the error. Is this the right way to do this, and why does it work? Should I make a habbit of just declaring any function that might be used in two .cpp files as inline?
View 5 Replies
ADVERTISEMENT
Dec 9, 2014
how to get this bug to go away and I am stressing about it. The project im working on simulates packet sending and receiving along with ROT13 encryption of the packets. The error lies within the .cpp file anywhere that I used IPHost.
header file
#ifndef IPHOST_H
#define IPHOST_H
#include <string>
#include <iostream>
class IPHost {
public:
//Default constructor defaults to 0.0.0.0
[code]...
error message:
In function 'ZStorSt13_Ios_OpenmodeS_':
line 11: multiple definition of 'IPHost::IPHost()'
line 11: first defined here
**this error repeats for every line in the .cpp in which IPHost is used.
View 5 Replies
View Related
Oct 31, 2012
I am trying to compile the files file1.c and file2.c using Mingw (gcc)
/////////////////////
header.h
////////////////////
#ifndef header
#define header
int variable;
#endif
[Code] ....
I would have expected a multiple defnition error when linking the two .c files. as in both the files, with the 'int variable' command, the variable 'variable' is defined (memory allocated) and during linking the linker doesnot know which variable to link to.
I get an error though when i use "int variable =123;" in the header file instead of the "int variable;" statement. i dont understand as in both the cases the variable is defined (memory is allocated) and the linker should give a multiple definition error.
View 8 Replies
View Related
May 6, 2014
I declared all functions in header file, such as:
bool readCase();
bool meshing();
bool readMesh();
bool calculateFlowfield();
bool readFlowfield();
bool calculateEvaporation();
And then I define them in separated .cpp files, each .cpp file include the header, but I got multiple definition error, why?
Even the int main() function, which only decalred and defined once got this error, why?
View 14 Replies
View Related
Nov 18, 2013
I have a question about multiple definition of class LoaderException.
I have such code:
LevelLoader.hpp
#ifndef LEVELLOADER_HPP
#define LEVELLOADER_HPP
[Code]....
I found way around this, but I would like to know why it shows multiple declarations.
My solution is to declare this class in function body(void LoadLevel()), just before the throw statement. But why can't I define it inside my namespace, but outside function?
View 6 Replies
View Related
Jan 16, 2014
I am writing a piece of code that requires me to display the last 1000 lines from a multiple text files (log files). FYI, I am running on Linux and using g++.
I have a log file from which - if it contains more than 1000 lines, I need to display the last 1000 lines. However, the log file could get rotated. So, in case where the current log file contains less than 1000 lines, I have to go to older log file and display the remaining. For e.g., if log got rotated and new log file contains 20 lines, I have to display the 980 lines from old log file + 20 from current log files.
What is the best way to do this? Even an outline algorithm will work.
View 6 Replies
View Related
Mar 22, 2013
So I have a rather large (for me) project, requiring me to have two .cpp files and a header. Anyway, both of the .cpp files #include the header file, but I recieve linker errors because the variables and functions in the header are declared and defined twice (once in each .cpp file). How am I supposed to do this?
View 8 Replies
View Related
Sep 24, 2014
We typically don't bother with massive, monolithic code files that get processed from top to bottom. In the Object Oriented world, code files don't mean much. In fact, in C#, I could have multiple classes defined in one file, or have one class split across several files.
View 7 Replies
View Related
Mar 23, 2014
I am struggling with the concept of having different ccp's and header files. I made a really bad example project for representation, but basically my question is are any of the #includes unnecessary that I have? Technically it functions, but if I am doing it wrong I want to prevent myself from starting bad habits in the future. My code just basically uses strings and sets a name and prints it. My code is really bad, but I wanted to just use includes in such a way for a quick example.
//MAIN.CCP
#include "functions.h"
using namespace std;
int main()
[Code]......
View 1 Replies
View Related
May 16, 2012
I am trying to run multiple source files but right after the first one finishes running the program closes and doesn't move on ...
View 2 Replies
View Related
Mar 7, 2013
How I can compile multiple source file in visual studio 2012 ???
View 1 Replies
View Related
Sep 7, 2013
I was trying out programs based on extern and as i understand, this is useful when accessing variables across multiple files having only one definition. But i tried a simple program as below without "extern" and thing seem to work when i expected it would fail during linking process
Code:
file5.c
1 #include <stdio.h>
2 #include "var.h"
3
4 int main() {
5
6 printf("
File5.c a = %d", a);
[Code] .....
As i have included "var.h" in all header files without extern, "int a" would be included in both the .c file and during linking, compiler should have thrown a warning or error message but it compiles file without any issue. Shouldn't var.h have the following "extern int a"?
View 8 Replies
View Related
Apr 9, 2013
I have a big un-editable program, A, which I need to run for like a 1000 different input files. It takes about 15 minutes for each file, so a little parallelisation wouldn't hurt.
I have installed openmpi and it works fine. I have made a small program, B, which selects an input file, moves it to another directory, calls program A with the path to the selected input file and then - when A is done - selects a new input file etc. It should loop until there are no more files in the initial directory.
The problem is this: When I have several processors they might pick the same file and that leads to errors. I have a working program, but it is not pretty.
Code:
#include <stdio.h>
#include <mpi.h>
#include <dirent.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char *argv[]) {
int num_procs, procs_id, i, exit;
struct dirent *ent;
[Code]...
Every time a processor tries to move a file that another processor has just moved, the output shows an error message before looping to the next file and trying again. It works, but it is a bit annoying. So my questions are:
1) Can I switch off the error message somehow?
2) Is there a better way to do this?
View 3 Replies
View Related
Aug 2, 2014
So say I create a header file which contains a list of structs, and I want to use these structs through out my source and some of my classes... how would I accomplish this?
When I try to do it via #include, I get re-definition errors, due to the nature of #pragma once. If I switch to #ifndef then I lack defenitions in files other than the source.
Is there a way to define things such as structs across multiple files, which doesn't lead to re-definition errors, and doesn't involve manually re-created all the structs for each file?
View 2 Replies
View Related
Apr 28, 2014
I am currently working on a C++ program for school. I am actually not finding too much difficulty in constructing the functions, enum-types, arrays and structs, however, I am finding great difficulty in using on ifstream variable to open multiple files.
I have posted the entire code that I have so far (even though I have pinpointed the issue to not properly opening the second file in ifstream).
I spent a couple of hours getting rid of certain functions/procedures, loops and variables and I get the same output (if what I removed doesnt crash it). I also get the same output whether I "open" the second file or not (meaning I removed all of the code for it and got the same output).
Here is the code (it's not finished because I am stuck on this file issue). It's a bit messy since I am now in debug mode versus program mode:
View 8 Replies
View Related
Oct 6, 2014
I have been working on code for quite some time and am able to successfully read in a text document and take certain words and information that I need. The issue is that I need to read in close to 100 plus documents and was wondering how I could read in the multiple documents. I thought about creating a structure of arrays and have each text document be an element and walk through taking each document but I am not sure how this works.
View 8 Replies
View Related
Jan 19, 2014
I am trying to get variables that are global to multiple files. I have mananged to make constant variables that are global but maybe not in the best way. In the header i have the constant variables being defined:
const int variable_Name = 5;
And the cpp file:
#include <iostream>
using namespace std;
#include "vars.h"
int main ( ) {
cout << variable_Name<< endl;
system ("pause");
return 0;
}
Is there a better way to do this and to make the variables able to be changed within the cpp files.
View 7 Replies
View Related
May 29, 2014
I am trying to create n number of files (n being an integer), by passing the name through a character array (and obviously changing its value at each iteration). But the problem is that the program compiles and executes but not a single file is created.
Here is my code snippet.
void file_phipsi(int m)
{
int a=0,n=0;
char *str1;
[Code].....
View 4 Replies
View Related
May 7, 2013
I am new to c++ programming i just want to know how to write the data into different files.Suppose my input files has 1-8 ids so each id data must be stored into each different file. And below is my code.
#include<fstream>
#include<iostream>
#include <cstdlib>
#include <algorithm>
#include<list>
#include <math.h>
#include<conio.h>
#include<string>
#define PI 3.14159265
using namespace std;
double angle;
ifstream indata;
ofstream outfile;
[Code] .....
View 1 Replies
View Related
Jan 11, 2013
I want to create a namespace named MyNS.
Can I define it in multiple files?
I mean:
file1.h
namespace MyNS {
const int File1 = 0;
} file2.h
namespace MyNS {
const int File2 = 1;
[Code] .....
View 6 Replies
View Related
Apr 14, 2014
I have attached my code below and I am stuck in what to do next to make an instance of the dateCls so I can use the instance to assign the open date. By instance I mean like create an instance of the class, like this: dateCls myFirstInstance; And everything in the dateCls I can access through the . operator. So far my code looks like this..what I should do? Lastly, I am using derived data from I think the bankAccountCls.
I need the main program to output this data:
dateCls openDate(01, 03, 2012, "open date");
saveAccountCls s1("1001", 300.50, 0.12);
s1.setDate(openDate);
s1.print();
s1.deposit(100, 01, 05, 2012);
s1.print();
s1.withdraw(50, 01, 10, 2012);
[code]....
View 8 Replies
View Related
Jul 31, 2014
I want to develop an application which can host multiple views of explorer (window), where as each window is totally separate from others. So that I can have multiple desktop views through my single explorer. Any built in feature in .NET ?
View 11 Replies
View Related
Aug 17, 2014
how to make subroutines and return multiple arrays.Before that, i wrote my program on matlab. could my program to be structured as following?
<header>
initial value of program;
subroutine1() {
calculating the first work;
return 2 or 3 arrays;
[code].....
View 14 Replies
View Related
Aug 23, 2014
I have two files that I want to compile:
main.cpp
Code:
#include <iostream>
using namespace std;
int ReadNumber();
void WriteAnswer();
[Code] .....
The compiler complains:
io.cpp||In function 'int ReadNumber()':|
io.cpp|3|error: 'cin' was not declared in this scope|
io.cpp||In function 'void WriteAnswer()':|
io.cpp|7|error: 'cout' was not declared in this scope|
io.cpp|7|error: 'endl' was not declared in this scope|
In io.cpp file, should I put the two statements ("include <iostream>" and "using namespace std") at the top, outside of the functions?
Or should I put the two statements inside each of the functions?
View 4 Replies
View Related
Sep 25, 2014
I am working on one application that requires extensive logging so I want to create a log file of each day during execution.
I tried easylogging++ but i am unable to use into multiple files. If i try to use in other file. I get compilation errors of using same functions or methods already defined.
How can i use macro to hide the implementation of logging in one class to other ??
View 1 Replies
View Related
Apr 18, 2013
I have managed to make a program that permutates a string with repetition.
I ran it to permutate "abcdefghijklmnopqrstuvwxyz1234567890" with a limit of 5 characters.
This took a little over 5 hours for my pc to process this and I ended up with a .txt 403MB in size. Needless to say I am unable to open this .txt in notepad without Notepad.exe not responding and me having to end the process.
So what I want to do is modify my code to break up the output in to several files rather than one. Possibly all permutations starting with a in one file, b in another, etc.
Here is my current code:
#include <iostream>
#include <string>
#include <sstream>
[Code]....
As you can see it currently appends permutation.txt with all output. I would like it to make files like this permut_5char_a.txt, permut_5char_b.txt, etc.
View 12 Replies
View Related
