libpng/docs/example.c

249 int check_if_png(char *file_name, FILE **fp)
254    if ((*fp = fopen(file_name, "rb")) == NULL)
258    if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
281    FILE *fp;
283    if ((fp = fopen(file_name, "rb")) == NULL)
287 void read_png(FILE *fp, int sig_read) /* File is already open */
306       fclose(fp);
314       fclose(fp);
327       fclose(fp);
335    png_init_io(png_ptr, fp);
585    fclose(fp);
742    FILE *fp;
748    fp = fopen(file_name, "wb");
749    if (fp == NULL)
762       fclose(fp);
770       fclose(fp);
781       fclose(fp);
790    png_init_io(png_ptr, fp);
1035    fclose(fp);