[SOURCE]
#include <stdio.h>
#include <stdlib.h>
#include <SDL/SDL.h>

SDL_Surface *screen;
int game_state;
int i;
int x;
int y;
int bytecount;

SDL_Surface *tiles[3];
int world[100*100];//map is 100x100

void init_tile()
{

     	tiles[0] = SDL_LoadBMP("gfx/water.bmp");
     	tiles[1] = SDL_LoadBMP("gfx/desert.bmp");
     	tiles[2] = SDL_LoadBMP("gfx/grass.bmp");


  	long size;
	int bytecount;
	int count;

  	
	FILE *f;
	f=fopen("maps/desert.map","r");
  	if (f==NULL) perror ("Error opening file desert.map");
  	else
  	{
    	fseek (f, 0, SEEK_END);
    	size=ftell (f);
    	//fclose (f);
	bytecount = size;  	
	}
	
     int world_index = 0;//stores our position in the world array
     while(i<bytecount)
     {

          int temp = fgetc(f)-48;//read a tile index from the file
          world[world_index] = temp;//store value from file in our world map array

          ++world_index;//move to next position in array
	i=i+1;
     }
fprintf(stderr, "\nLoad() is initialized\n\n");
game_state = 2;
}

//this is to be called from your game loop
//this is the same code from the earlier example
int world_x;//player's x position in the world
int world_y;//player's y position in the wolrd

//...insert code that get player input and updates world_x and world_y based on player input.

void draw()
{
	int x, y;

	int screen_x = 0;//x position on screen to draw to
	int screen_y = 0;//y position on screen to draw to

	//assume player character is at center of screen
	//find start position to draw from in tile array
	int start_x = world_x-10;//assume tiles are 32x32 and screen width is 640. 
	int start_y = world_y-7;//assume tiles are 32x32 and screen height is 480. 

	for(y = start_y; y < start_y+15; ++y)//again, assumes 15 rows
		{
			
          		for(x = start_x; x < start_x+20; ++x)//assumes 20 columns
          		{
               			//find out which tile we are currently looking for
               			int tile_index = world[y*20+x];
				

				printf("\ntile_index=%i", tile_index);

               			//use that value to get the tile from the tile set array
               			//SDL_Surface *curr_tile = tiles[tile_index];	
				
				/*
               			//draw the current tile.  sorry, dont know real funtion name
     				ShowBMP(curr_tile, screen, start_x, start_y);
				*/
				
				if(tile_index==0)
				{
					ShowBMP("gfx/water.bmp", screen, start_x, start_y);
				}
				
     				screen_x+=32;//move over 32 pixels because that is the width of one tile
				
     			}

     		//we have now finished drawing a row
     		screen_x=0;//reset screen x position to 0
     		screen_y+=32;//increment the screen y counter by 32 (height of one tile) so that we draw to the next row the next time through the loop
     		}
SDL_Delay(1000);
}

[/SOURCE]

char c;c = fgetc(f) - 48;while(c != EOF){  //Do something with c  //Get the next character  c  = fgetc(f) - 48;}

void ShowBMP(char *file, SDL_Surface *screen, int x, int y){	SDL_Surface *image;	SDL_Rect dest;	SDL_Surface *bbuf;    /* Load the BMP file into a surface */	    image = SDL_LoadBMP(file);    if ( image == NULL ) {        fprintf(stderr, "Couldn't load %s: %s\n", file, SDL_GetError());        return;    }    /* Blit onto the screen surface.       The surfaces should not be locked at this point.     */	dest.x = x;	dest.y = y;	dest.w = image->w;	dest.h = image->h;	SDL_BlitSurface(image, NULL, bbuf, &dest);	SDL_BlitSurface(bbuf, NULL, screen, &dest);    /* Update the changed portion of the screen */	SDL_UpdateRects(screen, 1, &dest);}