来来来，大神们讨论下这个问题

[登疯作极]

源由：偶然看到这个帖子http://blog.csdn.net/kevin_ut/article/details/6088489#reply，里面讨论的是C++与c的IO流到底哪个更快。代码很简单，如下：

void test_write()
{
	const int TEST_SIZE = 10000;
	const char* c_plus_write_file = "c_plus_write_file.txt";
	const char* c_write_file = "c_write_file.txt";

	cout << "Test size :" << TEST_SIZE << endl;
	//c++ style writing file  
	ofstream of(c_plus_write_file);
	assert(of);
	time_t start, end;
	start = clock();
	for (int i = 0; i < TEST_SIZE; ++i)
	{
		char tmp[10000];
		tmp[0] = char(i);
		of.write(tmp, 10000);
	}
	end = clock();
	of.close();
	cout << "C++ style: " << end - start << " ms" << endl;
	//c style writing file  
	FILE* fp = fopen(c_write_file, "w");
	start = clock();
	for (int i = 0; i < TEST_SIZE; ++i)
	{
		char tmp[10000];
		tmp[0] = char(i);
		fwrite(tmp, 1, 10000, fp);
	}
	end = clock();
	fclose(fp);
	cout << "C style: " << end - start << " ms" << endl;
	cin.get();
}

int main(){
	
	test_write();
	
		return 0;
	
}

结果如下：
左为g++，右为vs2013

[ipqtjmqj]

参考https://www.byvoid.com/blog/fast-readfile

[赵4老师]

无profiler不要谈效率！！尤其在这个云计算、虚拟机、模拟器、CUDA、多核 、多级cache、指令流水线、多种存储介质、……满天飞的时代！