1、打印内存地址

#include<stdio.h>
int main()
{
	int a;
	printf("%p\n",&a);   //%p打印地址，自己主动加前缀00
	printf("0x%x\n",&a); //%x以十六进制打印
	return 0;
}

0012FF44
0x12ff44

2、printf，sprintf，snprintf

原型：

int printf(const char *format, ...);
int sprintf(char *str, const char *format, ...);
int snprintf(char *str, size_t size, const char *format, ...);

snprintf将字符串最多复制 size-1 个字符到目标串中。

#include<stdio.h>
int main()
{
	char a[20];
	char *p = "Hello,iot_xiaohe";
	sprintf(a,"%s",p);
	printf("sprintf a is: %s\n",a);
	snprintf(a,10,"%s",p);
	printf("snprintf a is: %s\n",a);
	return 0;
}

sprintf a is: Hello,iot_xiaohe
snprintf a is: Hello,iot