Summary

• To send data to/from an external file the file must be connected to a stream.
• A stream is a sequence of characters and is connected to a device or a file.
• If streams other than the standard input streams cin and cout are used then the file fstream.h must be included in the program.
• Streams must be declared. Input streams are declared as having type ifstream and output streams as having type ofstream.
• A file is connected to a stream using the open(filename) member function of the stream. Failure of the open(filename) function is tested by the fail() member function of the stream. End of file condition is tested by the eof() member function of the stream. A stream (and the associated file) is closed by using the close() member function of the stream.