关于结构体类型数据的强制类型转换

有如下结构体定义: typedef struct cemsg { uchar dl; uchar mg; uchar data[10]; }CEMSG; typedef struct msg{ uchar id; uchar cmd; uchar byte[4]; }MSG; typedef struct msg_p{ uchar id; uchar cmd; uchar far * ptr; }MSG_P; void ap_getmsg(MSG *d_OsMsgPtr,CEMSG *d_Ce