void bufchain_prefix(bufchain *ch, void **data, int *len);
void bufchain_consume(bufchain *ch, int len);
void bufchain_fetch(bufchain *ch, void *data, int len);
void bufchain_prefix(bufchain *ch, void **data, int *len);
void bufchain_consume(bufchain *ch, int len);
void bufchain_fetch(bufchain *ch, void *data, int len);