26     int i_width, i_height, maxval;
    37     if (fscanf(input, 
"P6 %d %d %d", &i_width, &i_height, &maxval) != 3)
    44             (
"PNG: input file has incorrect dimensions: expected: %dx%d got: %dx%d",
    48         for (x = 0; x < 
png.
width; x++, p++) {
    74     int i_width, i_height, maxval;
    81     mask_name[strlen(mask_name) - 2] = 
'g';
    83     input = fopen(mask_name, 
"rb");
    85         G_fatal_error(
"PNG: couldn't open input mask file %s", mask_name);
    87     if (fscanf(input, 
"P5 %d %d %d", &i_width, &i_height, &maxval) != 3)
    94             (
"PNG: input mask file has incorrect dimensions: expected: %dx%d got: %dx%d",
   100         for (x = 0; x < 
png.
width; x++, p++) {
   103             int k = fgetc(input);
   105             k = k * 255 / maxval;
 void void void void G_fatal_error(const char *,...) __attribute__((format(printf
GRASS png display driver - header file. 
void G_free(void *)
Free allocated memory. 
unsigned int png_get_color(int r, int g, int b, int a)
char * G_store(const char *)
Copy string to allocated memory.