#include <gphoto2/gphoto2-abilities-list.h>
#include <gphoto2/gphoto2-camera.h>
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
 * \brief Returns a unique id for the camera driver.
 *
 * \param id a #CameraText
 * \return a gphoto2 error code
 *
 **/
typedef int (* CameraLibraryIdFunc)        (CameraText *id);
/**
 * \brief Adds the abilities of the supported models to the supplied list.
 *
 * \param list a #CameraAbilitiesList
 * \return a gphoto2 error code
 *
 **/
typedef int (* CameraLibraryAbilitiesFunc) (CameraAbilitiesList *list);
/**
 * \brief Initializes the camera.
 *
 * \param camera a #Camera
 * \param context a #GPContext
 * \return a gphoto2 error code
 *
 * The camera driver will establish a first connection
 * to the camera and configure the camera variable (i.e. using
 * #gp_filesystem_set_list_funcs or #gp_port_get_settings).
 typedef int (* CameraLibraryInitFunc)      (Camera *camera, GPContext *context);
/**
 * If you want to write a camera library, you need to implement
 * the following three functions. Everything else should be declared
 * as static.
 **/
int camera_id        (CameraText *id);
int camera_abilities     (CameraAbilitiesList *list);
int camera_init     (Camera *camera, GPContext *context);
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __GPHOTO2_LIBRARY_H__ */


我想问一下int camera_id        (CameraText *id);这个是不是函数是camera_id   然后他的参数是后面（）里面的东西？那个CameraText是数据类型？ *id 又代表什么？

typedef int (* CameraLibraryInitFunc)      (Camera *camera, GPContext *context);这一句又是什么意思？我知道typedef int real 是相当于用real可以代替int  那上面那句话是什么意思？又高手能解释下吗？谢谢了