Problem with loading PPM

Hello,

i´m trying load two ppm files and show the first image with glDrawPixels, but i´m only getting a white screen. This is the Code:

#include "../common/cg_common.h"
#include <iostream>
#include <fstream>
#include <string>

GLubyte* first_image;
GLubyte* second_image;
int win_width, win_height;

void skipComment(FILE *fin)
{
    char buf[120];
    
    while (true) {
       fscanf(fin, "%1s", &buf);
       if (buf[0] != '#') { 
           ungetc(buf[0], fin); 
           return; 
       }
       else fgets(buf, 120, fin);
    }
}

GLubyte *readPPM(FILE *fin, GLsizei *wid, GLsizei *ht)
{
    GLubyte  *bytes;
    char cookie[3];
    int width, height, maxComp;
    int n, r,c;
  
    fscanf(fin, "%2s", &cookie);
    
    if (strcmp("P6", cookie)) 
        return NULL;
    skipComment(fin);
    fscanf(fin, "%d", &width); *wid = width;
    skipComment(fin);    
    fscanf(fin, "%d", &height); *ht = height;
    skipComment(fin);        
    fscanf(fin, "%d", &maxComp);
    
    if (maxComp > 255) 
        return NULL;
    fgetc(fin);    
    
    bytes = (GLubyte  *) malloc(width*height*3);
    if (bytes == NULL) 
        return NULL;

    for (r=0; r < height; r++)
      for (c=0; c < width; c++) {
         bytes[3*(r*width + c)] = fgetc(fin); 
         bytes[3*(r*width + c)+1] = fgetc(fin); 
         bytes[3*(r*width + c)+2] = fgetc(fin);
         //std::cout << "Rot: " << bytes[3*(r*width + c)] << " Gelb: " << bytes[3*(r*width + c)+1] << " Blau: " << bytes[3*(r*width + c)+2] << std::endl;
      }
    
    return bytes;
}

void initView() {
    glMatrixMode (GL_PROJECTION);
    glLoadIdentity();
    gluOrtho2D(0, 256.0, 0, 256.0);
    glMatrixMode(GL_MODELVIEW);
}

void init() {
    GLsizei width;
    GLsizei height;
    std::string filename = "image1.ppm";
    
    GLubyte* image = readPPM(fopen(filename.c_str(),"r"),&width,&height);

    if(image != NULL)
        first_image = image;
    else
        std::cout << filename << " konnte nicht richtig geladen werden " << std::endl;

    filename = "image2.ppm";
    
    image = readPPM(fopen(filename.c_str(),"r"),&width,&height);

    if(image != NULL)
        second_image = image;
    else
        std::cout << filename << " konnte nicht richtig geladen werden " << std::endl;

    win_height = height;
    win_width = width;

    initView();
}

void initGL() {
    glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // black background
}

void display() {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glDrawPixels(win_width,win_height,GL_RGB,GL_UNSIGNED_BYTE,first_image);

    glFlush();
}

void reshape(int /*width*/, int /*height*/) {
    
}

void key(unsigned char k, int /*x*/, int /*y*/) {
    if (k == 27)
        exit(0);
}

// Main function for bringing it all together
int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_RGB);
    glutInitWindowSize(256, 256);
    glutCreateWindow("Aufgabe 3.6");

    initGL();
    init();

    // setup GLUT callbacks
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutKeyboardFunc(key);
//    glutIdleFunc(display);  // if continuous animation is required

    glutMainLoop(); // start the main event loop
}

These are the two images:
http://www.file-upload.net/download-4318262/two_images.zip.html

I have no Idea what i´m doing wrong :frowning:

thank you!

EDIT: Okay i think i found the failure. The read method reads only -1 after a few correct numbers