static int fd_write(BIO *h, const char *buf, int num);
static int fd_read(BIO *h, char *buf, int size);
static int fd_puts(BIO *h, const char *str);
static int fd_write(BIO *h, const char *buf, int num);
static int fd_read(BIO *h, char *buf, int size);
static int fd_puts(BIO *h, const char *str);