c指標作為引數傳遞以及指標的指標
阿新 • • 發佈:2018-11-14
#include "stdio.h" void pointer(int *p) { int a = 11; printf("\n\nEnter function"); printf("\nthe p is point to %p , addr is %X, *p is %d",p , &p, *p); *p =11; printf("\nthe p is point to %p , addr is %X, *p is %d",p , &p, *p); p = &a; printf("\nthe p is point to %p , addr is %X, *p is %d",p , &p, *p); printf("\nfunction return\n"); } int main() { int b =22; int *p = &b; printf("the b address %X\n",&b); printf("the p is point to %p , addr is %X, *p is %d",p , &p, *p); pointer(p); printf("\nthe p is point to %p , addr is %X, *p is %d\n",p , &p, *p); }
#結果 the b address 28FF3C the p is point to 0028FF3C , addr is 28FF38, *p is 22 Enter function the p is point to 0028FF3C , addr is 28FF20, *p is 22 the p is point to 0028FF3C , addr is 28FF20, *p is 11 the p is point to 0028FF0C , addr is 28FF20, *p is 11 function return the p is point to 0028FF3C , addr is 28FF38, *p is 11
#include "stdio.h"
void GetMemory(char **p,int num)
{
*p=(char*)malloc(sizeof(char)*num);
}
void main()
{
char *str=NULL;
GetMemory(&str,100);
strcpy(str,"hello\n");
printf(str);
}
參照來源: https://www.cnblogs.com/WeyneChen/p/6672045.html