static int r_forward(RSFD rfd, void *buf, TERMID *term, const void *untilbuf);
static void r_pos(RSFD rfd, double *current, double *total);
static int r_read_not(RSFD rfd, void *buf, TERMID *term);
static int r_forward(RSFD rfd, void *buf, TERMID *term, const void *untilbuf);
static void r_pos(RSFD rfd, double *current, double *total);
static int r_read_not(RSFD rfd, void *buf, TERMID *term);