Include c files using z88dk

Question

I want to split a program developed in c using z88dk in several .c files and I do not know how.

I have these files:

1. test.c: The main file with the "main" method.
2. test2.c: An auxiliar file with the "AuxFunction" method.
3. test3.h: The header definition for test2.c

I Build with this command: D:\Spectrum\z88dk\bin\zcc.exe +zx -lndos -create-app test.c test2.c -o test

The error reported from zcc is this: Error at module 'test2': symbol '_AuxFunction' already defined in module 'test2'

There are the sources:

test.c

/* test.c file */

#include <stdio.h>
#include "test2.h"

void main(){
    printf("Include test 1.1!\n");
    printf(AuxFunction("Hello"));
}

test2.c

/* Test2.c file */

char* AuxFunction(char* txt){
    return txt;
}

test2.h

/* test2.h file */

char* AuxFunction(char*);

Any link, help or suggestion will be welcome!

Thanks for your time!

Answer 1

As Mick suggested, declare AuxFunction as extern in the header file. This works for me using d88zk version 1.8, zcc version 2.57 (which is the version in the debian repos). Declaring functions 'extern' is generally useless in any compiler from the last 20 years. I guess d88zk, despite appearing to be an active project, needs to be treated as a legacy C compiler.

test2.h

/* test2.h file */

extern char* AuxFunction(char*);