calling a function from a .h file

file1.c => includes file1.h

file1.h => has a struct:

typedef struct {
  unsigned char *start;
  unsigned int startInt;
}debugPrint;

file1.c => creates a struct object:

debugPrint dp;

file1.c => an int is given into struct:

dp.startInt = 10;

file1.c => has a function:

void function1(debugPrint dp) {
  printf("%d", dp.startInt);
}

file2.h => has a function call to file1.c function which is declared before the call:

void function1(void);

function1();

Questions is:

• Is it ok that the file2.h calls a function from file1.c
• how can i pass the dp.startInt value to file2.h so that the value 10 that was set into dp.startInt in file1.c can be used in the funtion call in file2.h ?

It is needed to be called from file2.h since this file handles dynamic variable exchange between a html page and the file2.h file => data from file2.h function call via file1.c is sent to Html page. But i wont go more into the passing variable to html page since i don't know how it is made. It is a mechanism of openPicus web server example.

But if you know a good solution for this one. i would appreciate it. I'm not so familiar with this kind of code so that is also an issue here :)

But since i think this description is not good enough, here is the files:

file1.c:

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include "test1.h"

// Define printStruct
void printStruct (debugPrint dp) {
    printf("%u", dp.startInt);
}

int main ()
{
    dp.startInt = 10;
    getch();
}

file1.h:

typedef struct {
    // For the motorEncoder value
    unsigned char filename[20];
    char ownMsg[10];
    unsigned char *start;
    unsigned char *timeInSeconds;
    unsigned char *distanceInCm;
    unsigned char *numberOfShots;
    unsigned char *shutterCompensation;
    unsigned char *direction;
    unsigned char *cancel;
    unsigned char *dutyCycle;
    unsigned int cancelInt;
    unsigned int startInt;
    unsigned int dutyCycleInt;
    unsigned int directionInt;
}debugPrint;

// Create struct object called dp
debugPrint dp;

// declare printStruct
void printStruct (debugPrint dp);

file2.h: (this file is totally needed to pass the dynamic values) I didn't put any includes since im not sure how i should include the .h files and from where i should include them.

// Call printStruct function
printStruct(dp);

part of file2.h actual code: (AND YES file2.h A HEADER FILE). FOR ME THIS SEEMS LIKE THE FUNCTIONS ARE FIRST DECLARED AND THEN ONE OF THEM IS USED IN THE H FILE => the HTTPPrint() function from where a function called HTTPPrint_stepCounter(); is called. That function is defined then in file1.c and it just prints some dynamic data to a http page. And as said this is how openPicus has done it and i am just trying to modify it.

void HTTPPrint(DWORD callbackID);
void HTTPPrint_led(WORD);
void HTTPPrint_stepCounter(void);

void HTTPPrint(DWORD callbackID)
{
    switch(callbackID)
    {
        case 0x00000017:
            HTTPPrint_led(0);
            break;
        case 0x00000059:
            HTTPPrint_stepCounter();
            break;
        default:
            // Output notification for undefined values
            TCPPutROMArray(sktHTTP, (ROM BYTE*)"!DEF", 4);
    }

    return;
}

void HTTPPrint_(void)
{
    TCPPut(sktHTTP, '~');
    return;
}

You claim that file2.h contains:

void function(void);

function1();

But these lines refer to two different functions.
^{This problem is now fixed; both names are function1}

If the function1(); appears outside any function, it is a (very sloppy) function declaration, not a function call. If it is inside some function, what is that function definition doing inside the header file. It would need to be an inline function to have much legitimacy.

^{The problem below is now fixed; the types are consistent.}
Additionally, you say: an integer is given into struct: dp[1].startInt = 10;. The compiler complains that you shouldn't assign integers to pointers (since startInt is declared as a pointer, not an int). You need to get your code to compile without such complaints.

... There are two versions of the structure defined, one at the top of the question where startInt is an unsigned int *startInt; and one later on where the declaration is unsigned int startInt. Please make your question self-consistent! ...

^{This problem has been fixed now; dp is a simple structure.}
Also note that you created debugPrint dp[1]; so your initialization is trampling out of bounds; the maximum valid index for the array is 0.

If code in file2.c needs to access the internals of the structure type declared in file1.h, the header file1.h should be included in file2.c. You can declare your dp array in the header too. A header should include other headers only if the functions it defines expose types defined in the other headers. For example, if the structure defined in file1.h included a FILE *db_fp; element, then file1.h should #include <stdio.h> to ensure that the code in file1.h would compile regardless of what else the code using file1.h includes.