C语言结构体问题，为何有误

Question

typedef struct ltbl
{
struct ltbl* pNxt; /* 指向链表中后一个元素的指针 /
int note;
int empty;
int effect; / KEY VALUE /
int Total;
char *PATH; / dizhi */
}LTBL;

char *Z_path = NULL;
LTBL * p = NULL;

Z_path = (char*) malloc( (length + strlen(FileInfo.name) + 1) * sizeof(char) );

P->PATH = Z_path; //为啥有误？？？？

Answer 1

char *Z_path = NULL;
LTBL * p = NULL;

Z_path = (char*) malloc( (length + strlen(FileInfo.name) + 1) * sizeof(char) );
P->PATH = Z_path; //为啥有误？？？？

因为p还是NULL，没有malloc分配空间