Frustrated. How do I use void display(char * str) in a header file?

[bent]

Ugh.

I am taking a c++ foundations course, and all was well until the moment came where I had to break my prototypes out into .h files. Until this point, all my prototyping has been done with ints, doubles, etc. - char seems to be different and vexing.

test.h

void display(char* str)
---------------------------------------------
int main()
{
#include "test.h"
char str[] = "hello";
display();
}

At this point I get an error on compile and nothing I have done, or none of the reference material I have at my disposal is fixing the prolem.

HELP!

[ilikepython]

Ugh.

I am taking a c++ foundations course, and all was well until the moment came where I had to break my prototypes out into .h files. Until this point, all my prototyping has been done with ints, doubles, etc. - char seems to be different and vexing.

test.h

void display(char* str)
---------------------------------------------
int main()
{
#include "test.h"
char str[] = "hello";
display();
}

At this point I get an error on compile and nothing I have done, or none of the reference material I have at my disposal is fixing the prolem.

HELP!

Your include commands should be at the top of the file and don't forget to add a semicolon after your prototype. Also, your display function takes a char pointer but you aren't passing it any. Make sure that you actually have the body for the display function.

#include "test.h"
 
int main()
{
    char str[] = "Hello";
    display(str);
    return 0;
}
 

Don't get confused by characters, they are just another data type like ints or doubles.

[bent]

Thanks! - that was the vital piece -

I am now getting a return value of ''__Z5helloPc' - which is not right.

The whole program looks like:

#include <iostream>
using namespace std;
#include <limits>
int main()
{
#include "testing.h"
    char str[] = "hello";
    hello(str );
 
 
    cout << str[0]
        << str[1]
        << str[2]
        << str[3]
        << str[4]
        << endl;
 
 
    cout << str[4]
        << str[3]
        << str[2]
        << str[1]
        << str[0]
        << endl;
 
    return 0;
}
 

I am not sure where the garbage is coming from.

it should return "hello
olleh"

Which it does when the function is in main().

[Savage]

Thanks! - that was the vital piece -

I am now getting a return value of ''__Z5helloPc' - which is not right.

The whole program looks like:

#include <iostream>
using namespace std;
#include <limits>
int main()
{
#include "testing.h"
    char str[] = "hello";
    hello(str );
 
 
    cout << str[0]
        << str[1]
        << str[2]
        << str[3]
        << str[4]
        << endl;
 
 
    cout << str[4]
        << str[3]
        << str[2]
        << str[1]
        << str[0]
        << endl;
 
    return 0;
}
 

I am not sure where the garbage is coming from.

it should return "hello
olleh"

Which it does when the function is in main().

It's probably coming from function.

And what do u mean by:

"Which it does when the function is in main()."?

Ur hello function is currently in main.

Please can u give us more info..

Savage

[bent]

It's probably coming from function.

And what do u mean by:

"Which it does when the function is in main()."?

Ur hello function is currently in main.

Please can u give us more info..

Savage

my testing.h header file contains:

void hello(char* str);
 

if I put

char * str = new char[5];
str = "hello";
 

in the main body of my program, it returns my expected results. It is when I include the header file, I get the garbage return value.

[Savage]

my testing.h header file contains:

void hello(char* str);
 

if I put

char * str = new char[5];
str = "hello";
 

in the main body of my program, it returns my expected results. It is when I include the header file, I get the garbage return value.

Can we see function hello definition?

Savage

[bent]

Can we see function hello definition?

Savage

Savage,

This is where I am getting ignorant. Function hello only exists as a prototype in the header file. everything else I have posted is the entirety of the program.
I am a rank beginner at OOP, so please forgive me if I am missing something or mis-understanding something.

The goal of the program is to use pointer arithmatic to display the string "hello" forwards and bachwards . As far as coding it without using the header file, I am successful.
So far, I have been unable to include the header in any meaningful way. Hence my frustration.

[Savage]

Savage,

This is where I am getting ignorant. Function hello only exists as a prototype in the header file. everything else I have posted is the entirety of the program.
I am a rank beginner at OOP, so please forgive me if I am missing something or mis-understanding something.

The goal of the program is to use pointer arithmatic to display the string "hello" forwards and bachwards . As far as coding it without using the header file, I am successful.
So far, I have been unable to include the header in any meaningful way. Hence my frustration.

I allready know all that and this is probably ur problem:

int main()
{
#include "testing.h"
    char str[] = "hello";
    hello(str );

As ilikepython said ur include commands should be at the top of the code.

(Sorry,didn't noticed it when I was looking before few minutes)

Savage

[bent]

int main()
{
#include "testing.h"
    char str[] = "hello";
    hello(str );
 

The problem, it appeared was on the final line above, with referenced the prototype, but didn't have any play with the variables. Removing that line fixed the output.

Thanks!

[Savage]

int main()
{
#include "testing.h"
    char str[] = "hello";
    hello(str );
 

The problem, it appeared was on the final line above, with referenced the prototype, but didn't have any play with the variables. Removing that line fixed the output.

Thanks!

Allways a pleasure..

Savage