gcc #define 学习记录

//test.c 

#include <stdio.h>
#include <stdlib.h>

//字符串化运算符
#define EXPAND(name) ({ \
		printf("%s\n", #name); })

//二元运算符 ## 将左和右操作数结合成一个记号

#define test(name, index) ( { \
		int i, len = sizeof(name ## index) / sizeof(int); \
		for (i = 0; i < len; i++) \
		{                          \
		printf("%d\n", name ## index[i]);  \
		}}) 

int main(int argc, char *argv[]) {
	EXPAND(Test);
	EXPAND("\"TEST");

	EXPAND(__DATE__);
	EXPAND(__TIME__);
	EXPAND(__FILE__);
	EXPAND(__LINE__);
	EXPAND(__func__);
	int x1[] = { 1, 2, 3 };
	int x2[] = { 11, 22, 33, 44, 55};
	test(x, 1);
	test(x, 2);

	return 0;
}

　　运行效果如下：

 $ ./defind_test
 Test
 "\"TEST"
 __DATE__
 __TIME__
 __FILE__
 __LINE__
 __func__