Classic/Legacy CodeWarriorのトピックRe: Dividing the code in various .c files

Dividing the code in various .c files for PowerPC program

xainub — Sun, 10 Jun 2007 19:47:54 GMT

I am new to code warrior.

I am building a C application on powerpc,

Since my main code is very big with lots of fuctions, there our some global structures which these functions update after recieving values from UARTs.

I want to divide my code in various .C files, as in the global structures stay in main and the functions are grouped in various .c files. They update the data structures they way they do it in main.

Please help me how this can be done.

~Cheers

Message Edited by J2MEJediMaster on 2007-06-11 10:16 AM

Re: Dividing the code in various .c files

xainub — Mon, 11 Jun 2007 13:02:48 GMT

Actually I don't know how to implement code division in various C files in Code Warrior

Re: Dividing the code in various .c files

sjmelnikoff — Mon, 11 Jun 2007 16:15:48 GMT

Dividing up a C program into separate files is a fundamental part of programming in C. I strongly suggest you find a good book or website on C, and look up how to structure code in this way.

Steve.

Re: Dividing the code in various .c files for PowerPC program

xainub — Tue, 12 Jun 2007 02:10:14 GMT

I have done it before,

but Actually I was having problems with extern this time

Re: Dividing the code in various .c files for PowerPC program

sjmelnikoff — Tue, 12 Jun 2007 15:48:59 GMT

Well, globals are best avoided. But if you must:

Header.h:

extern unsigned int MyVar; /* Declaration */

File1.c

#include "Header.h"

...

unsigned int MyVar; /* Definition */

...

MyVar = 3; /* Use */

File2.c

#include "Header.h"

...

MyVar = 3; /* Use */

Steve.

Re: Dividing the code in various .c files for PowerPC program

xainub — Tue, 12 Jun 2007 22:16:06 GMT

Thanx alot, I will try keeping all in one header file and adding it in all,

Would it be a okay even if i declare them in the common header file rather than main.c?

Re: Dividing the code in various .c files for PowerPC program

sjmelnikoff — Wed, 13 Jun 2007 15:22:56 GMT

The declaration (the bit with the extern) must be visible to any source (.c) file which uses the variable, so the common practise is to put it in a header (.h) file, and #include that header wherever the variable is required. The definition acts just like a function prototype.

The definition can only exist in one place, as it allocates the space for the variable, so must be in a source (.c) file. In that respect, it behaves like a function body.

Again, I strongly recommend that you find a good C reference, and read up on this subject.

Steve.

Re: Dividing the code in various .c files for PowerPC program

xainub — Wed, 13 Jun 2007 22:14:55 GMT

Hey, thanx alot, I tried it and its working now

I was reading few tutorials, but i had this query and which clearly wasn't answered anywhere.

I will do more studyin on this.

Thanx again.