c++写日志文件的操作

 1 class LogFile
 2 {
 3 public:
 4   static LogFile &instance();
 5   operator FILE *() const { return m_file; }
 6 private:
 7   LogFile(const char *filename)
 8   {
 9      m_file = fopen(filename, "a+");
10   }
11   ~LogFile()
12   {
13      fclose(m_file);
14   }
15   FILE *m_file;
16 };
17
18 LogFile &LogFile::instance()
19 {
20    static LogFile log("AppLog.txt");
21    return log;
22 }
23
24 //用的时候可以这么写：
25 fwrite("abc", 1, 3, LogFile::instance());