[C++] 파일 입출력

예제

• 코드

   #include <fstream>
   #include <iostream>
   #include <string>
      
   using namespace std;
      
   void read(string fileName) {
   	ifstream is(fileName.c_str());
   	is.seekg(0, is.end);
   	long size = is.tellg();
   	is.seekg(0);
      
   	char buffer[size];
      
   	if (is.read(buffer, size)) {
   		cout << "read ok" << endl;
      
   		cout << "------" << endl;
   		cout << buffer << endl;
   		cout << "------" << endl;
   	} else {
   		cout << "read fail" << endl;
   	}
   }
      
   void write(string fileName, string buffer) {
   	ofstream os(fileName.c_str(), ofstream::trunc);
      
   	if (os.write(buffer.c_str(), buffer.size())) {
   		cout << "write ok" << endl;
   	} else {
   		cout << "write fail" << endl;
   	}
   }
      
   int main() {
   	string fileName = "./test.txt";
   	string buffer = "abc";
   	write(fileName, buffer);
   	read(fileName);
      
   	return 0;
   }
  

• 실행 결과

   write ok
   read ok
   ------
   abc
   ------