GLuint program_object;

void init()
{
const char *vertex_source =
   "void main(void) {"
   "  gl_Position = ftransform();"
   "  gl_BackColor = gl_FrontColor = gl_Color;"
   "  gl_TexCoord[0].xy = gl_MultiTexCoord0.xy;"
   "}";
const char *fragment_source =
   "uniform sampler2D sample_0;"
   "void main(void) {"
   "  gl_FragColor = gl_Color;"
   "  gl_FragColor *= texture2D(sample_0, gl_TexCoord[0].st);"
   "}";


   GLuint vertex_shader = glCreateShader(GL_VERTEX_SHADER);
   glShaderSource(vertex_shader, 1, &vertex_source, NULL); 
   glCompileShader(vertex_shader);

   GLuint fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
   glShaderSource(fragment_shader, 1, &fragment_source, NULL);
   glCompileShader(fragment_shader);

   program_object  = glCreateProgram();
   glAttachShader(program_object, vertex_shader);
   glAttachShader(program_object, fragment_shader);
   glLinkProgram(program_object);

   glDeleteShader(fragment_shader);
   glDeleteShader(vertex_source);
}


   // for rendering
   glUseProgram(program_object);
   // draw here
   glUseProgram(NULL);



   // for cleanup
   glDeleteProgram(program_object);