How to use the data obtain in one C file to another C file?

[tommy_chai]

Hi guys,
First, I detect coordinates for left and right corners of a mouth in Corners.c and saved in struct Coordinate for 72 images.
How can I able to link it to another C file, let's say try5.c so that it can be used for template matching purpose when i execute 72 images in a loop in try5.c?
Sorry because I cannot provide the full program because it is a way too long to read. These are the parts which i think very important in order to solve the problem. Help from anyone will be appreciated.

Thank you very much.

Corners.c
struct Coordinate
{
	int x;
	int y;
};
susan_corners(in,r,bp,max_no,corner_list,x_size,y_size){
:
:
struct Coordinate left_corner, right_corner;
}

try5.c
:
:
#define NUM 72
:
main()
{
:
:
if((fp33 = fopen("facecolor_input.dat","r")) == NULL){
		printf("File input filename2  can not open\n");
		exit(1);
	}
	for(k=0;k<NUM;k++){
		fscanf(fp33,"%s",filename33[k]);
	}
	fclose(fp33);
:
:
for(total = 0; total<NUM; total ++){    
	
		printf("\nimage==>%d\n",(total+1));

/** read the color data from the file of input face image **/
		read_data_color(filename33[total],inpcolor);
:
:
/*     Template Matching   */
//example for eye template matching
             XX1=56;   // Left X coordinate for eye template
	YY1=44;
	XX2=164; //right X coordinate for eye template
	YY2=44;
// plf_x, plf_y, prg_x, prg_y are the left and right x & y coordinates from the full input image which has been obtained in Corners.c
	affine_recog_a(plf_x, plf_y, prg_x, prg_y, XX1, YY1, XX2, YY2);
	cross_correlation_recog_a(TEMPLATE_a, image_out_a, &CC1[0]);
:
:
}

Best regards,
Tommy