int (*source_add)(struct sr_session *session, void *priv, int events,
int timeout, sr_receive_data_callback cb, void *cb_data);
int (*source_remove)(struct sr_session *session, void *priv);
int (*send)(void *priv, const char *command);
int (*read_begin)(void *priv);
int (*read_data)(void *priv, char *buf, int maxlen);
int (*source_add)(struct sr_session *session, void *priv, int events,
int timeout, sr_receive_data_callback cb, void *cb_data);
int (*source_remove)(struct sr_session *session, void *priv);
int (*send)(void *priv, const char *command);
int (*read_begin)(void *priv);
int (*read_data)(void *priv, char *buf, int maxlen);