Header files included in multi .cpp files

Question

Hello.

I followed a simple example as below. But compile failed.

Could you please have a look and give me some suggestion.

vs2010 console application used.Thank you.

Error message

pgm.h(11): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
pgm.h(11): error C2143: syntax error : missing ',' before '&'
1>  multi_fct.cpp
pgm.h(11): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
pgm.h(11): error C2143: syntax error : missing ',' before '&'
1>  ch3_p96.cpp
pgm.h(11): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
pgm.h(11): error C2143: syntax error : missing ',' before '&'
ch3_p96.cpp(24): error C2664: 'prn_info' : cannot convert parameter 1 from 'const char [8]' to 'const int'
1>          There is no context in which this conversion is possible
ch3_p96.cpp(26): error C3861: 'fct1': identifier not found

pgm.h

#include <iostream>
#include <cstdlib>
#include <string>

#define     N   3

void fctl(int k);
void fct2();
void prn_info(const string& pgm_name);

ch3_p96.cpp

#include "stdafx.h"

#include <iostream>

#include "pgm.h"

using namespace std;

int main()
{
    char ans;
    int  k, n = N;

    cout << "This program does not do very much.\n";
    cout << "Do you want more information?\n";
    cout << "Enter either y or Y is yes.\n" << endl;

    cin >> ans;

    if (ans == 'y' || ans == 'Y')
        prn_info("ch3_p96");    // multi_main
    for (k = 0; k < n; ++k)
        fct1(k);

    cout << "Best Regards!" << endl;

}

multi_fct.cpp

#include "StdAfx.h"

#include <iostream>
#include "pgm.h"

using namespace std;

void fct1(int n)
{
    int i;

    cout << "Hello from fct1()" << endl;
    for (i = 0; i < n; ++i)
        fct2();
}

void fct2()
{
    cout << "Hello from fct2()" << endl;

}

multi_prn.cpp

#include "StdAfx.h"

#include <iostream>
#include <string>
#include "pgm.h"

using namespace std;

void prn_info(const string& pgm_name)
{
    cout << "Usage:  " << pgm_name << endl;
    cout << "This program illustrates a   " << endl;
    cout << "Program is more than one file.    " << endl;
    cout << "In this example, a single" << endl;
    cout << ".h file is included at the" << endl;
    cout << "top of our three .cpp files." << endl;
    cout << "Thus pgm.h acts as the \"glue\"" << endl;
    cout << "that binds the program." << endl;
}

Answer 1

You need to namespace qualify string: std::string.

The compiler error is saying that it didn't find a type name, so it's guessing that string is an int, and continuing to try and parse your code.

Also, in one place you use fctl (fct lower-case-L) and in one place you use fct1 (fct one).

Answer 2

You need to qualify string:

void prn_info(const std::string& pgm_name);

It is in the std namespace. Please do not use using namespace std in a header file.