int recv_sideband(const char *me, int in_stream, int out);
ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max);
int recv_sideband(const char *me, int in_stream, int out);
ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max);