/* ustream_consume: remove data from the head of the read buffer */
void ustream_consume(struct ustream *s, int len);
/* ustream_consume: remove data from the head of the read buffer */
void ustream_consume(struct ustream *s, int len);
/* ustream_write: add data to the write buffer */
int ustream_write(struct ustream *s, const char *buf, int len, bool more);
int ustream_printf(struct ustream *s, const char *format, ...);
/* ustream_write: add data to the write buffer */
int ustream_write(struct ustream *s, const char *buf, int len, bool more);
int ustream_printf(struct ustream *s, const char *format, ...);