Thread: Header files

Hey guys,

I have 2 header files in my project and one them defines a struct type that the other header uses. If I include the first one in the second one, it thinks I'm tryign to redefine my struct. IE.
1st header: containes a struct definition
2nd header: has a function declaration that uses the strust

do I have to define the struct again in the 2nd one or is there another way?

If I just use the struct in the 2nd one, the function doesn't recognise it and gives me an undefined variable error.
The headers are included in alphabetical order.

Why don't you make your struct a class, and then include the function as a method of that class?

Just a thought from a noob.

I use the struct in another class. the function has to be called by the main separatelly. It's easier that way, I think. The function takes more argumetns then just the struct.

Add include guards to your header files. If you already have, post some code and the error.

One sec, gotta read about include guards.....

OK, I don't think I'm doing it right with the header guards. Here are the files:

Original header:

Code:

/*
*  Header File: EDFParse3.h
*
*/

# include <string.h>
# include <stdlib.h>
# include <ctype.h>
# include<cstdio>
# include <vector>
# include <iostream>
# include "stdafx.h"
  
using namespace std;

struct DataLine
{
	char Param[20];
	int Label, SFactor, SigBits;
	int Bit30, Bit31, Max, Min;

	DataLine()
	{
		Label=SFactor=SigBits=Bit30=Bit31=Max=Min=0;
		memset(Param, 0, sizeof(Param));
	};

} ;

class FSAD        //Fixed/Selectable Analog Data  
	{
	public:

		char Name[25];
		int nExpected;  // size = nExected*2+1
		std::vector < DataLine > vectDL;		
	}; 

 /*#ifdef __cplusplus
 extern "C" {
 #endif */

#ifndef EDFParse3_HPP
  
#define EDFParse3_HPP 


int FindWord(FILE *inp,char KeyWord[25], char *string);
int GetWord(FILE *inp, char *string);
void SkipWS(FILE *inp);
void ReadDataSec(FILE * inp, FSAD &Section , int nExpected);
        //void print_Struct( struct DataLine sec );
        //int ReadSection(FILE * inp, struct DataLine Sec[], int nExpected);
FILE* OpenFileEDF(FILE *out);


#endif

the header that uses the previous one:

Code:

# include <stdio.h>
# include <math.h>
# include <STDLIB.H>
# include "EDParse3.hpp"

# define BIT01 0X00000001
# define BIT02 0X00000002
# define BIT03 0X00000004
# define DATAMASK18 0XFFFFC00

#ifndef MakeArincAnalog_H 
#define CreateWord_H 

int MakeLabel(int number /*Input Octal label*/);
int MakeArincWordAnalog(DataLine Line, float value,  int word);
//float DecodeArincAnalog(int word, float scale);
#endif

and the main:

Code:

.............
#include "BAFParse.h"
#include "EDFParse3.hpp"
#include "MakeArincAnalog.h"
....................

one of the errors:

Code:

fatal error C1083: Cannot open include file: 'EDFParse3.hpp': No such file or directory
MakeArincWordAnalog.cpp

The include guards should cover the entire header file. So
#ifndef EDFParse3_HPP
#define EDFParse3_HPP

should be at the top of the file and the #endif should be at the bottom.

Your error is probably because you named your header file EDFParse3.h instead of EDFParse3.hpp. Use .h or .hpp, but be consistent.

I changed the position of the header guards, and I renamed the actual file to EDFParse3.hpp and that did the trick.

Thanks a lot guys,

AS.