void from_backend(int is_stderr, char *data, int len)
int from_backend(int is_stderr, char *data, int len)
void from_backend(int is_stderr, char *data, int len){    while (len--) {	if (inbuf_head >= INBUF_SIZE)	    term_out();	inbuf[inbuf_head++] = *data++;    }}