Thread: How to Link Various Files

So, I have this college project, and I need to make a POS application.

My POS (Point of Sale) has two working modes, as the supervisor, and as an employee.

To make it simpler, me and my work-mate decided to make various .c programs, to make it simpler to read the code, and possibly understand what's wrong.

So, we have the main.c file, in which you access to the interface, depending on how you run the program command.

So far, so good, but, since we want the interface to be a separated file ( interface.c ) how do I, link it to the main.c? It is simply creating an interface.h with the function headlines and including it in main.c?? And how would I compile that with gcc?

Another question, the project bases a lot on .xml file reading/writing/scanning data, can I just type:

Code:

 fopen = ("Database.xml", "w");

?

And, other thing, that is this "atoi" function??

Thanks in Advance!!

Originally Posted by MacGyver

You can open an XML file in text mode, but you might want to make it easier on yourself by having a library read the XML. Either way, you can do it anyway you want.

Look up the proper string permission requests for reading/writing/etc. for fopen(). Make sure you don't trash the contents of the file and lose the data by opening it for destructive writing.

Okay, I never heard of this in College, so.. I can just make a file, say "read_xml.c" and make a read_xml.h file?

Well, considering I have, numbers, and characters to write/replace/read, if I just make the function write/read between the "<" ">" and "</" tags, would I be fine?

Okay, thanks a lot, MacGyver, guess I'll have to study a bit more of file reading/writing,

Specially the part where the function finds a line and write in a specific spot.

To make it simpler, me and my work-mate decided to make various .c programs, to make it simpler to read the code, and possibly understand what's wrong.

So, we have the main.c file, in which you access to the interface, depending on how you run the program command.

Regrading your first question, if you wanted to link you interface.c file into your main. What you have to do just create an object of your interface and then link the object file into your mian. So for example

Code:

gcc -c -o interface.c

gcc -o main main.c interface.o

That will create you main as your exe file and just run your main.

ssharish

Okay, but still I need to create the "interface.h" file and write the:

Code:

#include "interface.h"

Where interface.c would have, for example, function A, which would create the menu, B which would read the file, and C, which would write on the file.

interface.h should only be:

Code:

 
#include<lib1.h>
#include<lib2.h>

A;
B;
C;

??

Originally Posted by Chinfrim

Okay, but still I need to create the "interface.h" file and write the:

Code:

#include "interface.h"

Where interface.c would have, for example, function A, which would create the menu, B which would read the file, and C, which would write on the file.

interface.h should only be:

Code:

 
#include<lib1.h>
#include<lib2.h>
 
A;
B;
C;

??

Your .h file would normally have all the function prototype and macros and all. What you have to do is include your .h file both in interface.c and main.c. And now create the interface.o file and now link the .o file to your main.c file. You might well need to provide the path for your header file as well. Like say for example

Code:

gcc -c interface.c interface.h

assuming that you have the .h file in the same dir.

ssharish

I tried with not including the header file while compiling, but i got an error message and decided to pass is as parameter to gcc. And everything went fine. May be the .h file path wasn't right.

So perhaps i should say to OP, if you have your .h file in the current directory don't include them while compiling.

ssharish

Meh, it's too much to learn in one week, while studying for another subjects, I guess I'll fail.. sigh.

Originally Posted by Chinfrim

Meh, it's too much to learn in one week, while studying for another subjects, I guess I'll fail.. sigh.

Why do you think, that way. Don't ever think you will fail. If you think that way you will definitely fail. Think positive.

ssharish

Originally Posted by MacGyver

Failing is up to you.

If you work on it slowly, a little day by day, you can do it in a week, depending on how much work there is.

Well, considering, I don't know how to exactly read from a file, and write in it, how to make dynamic structs, and this project is all about that, I have a long way to go.