File IO: Text vs Binary Files

File Input/Output (IO)

• File IO involves the transfer of data between secondary memory (hard disk) and main memory.

Text and Binary Files

• Text files are human-readable, storing data in terms of text.
• Binary files are not human-readable, storing data in terms of 0s and 1s.
• In text files, newline (\n) characters are converted into carriage return-linefeed combinations before being written to disk.
• In binary files, these conversions do not take place.
• Text files use a special character (ASCII value 26) to mark the end of the file, which is not present in binary mode files.
• In text files, text and characters are stored one character per byte, whereas in binary files, data is stored in its original format.

File Opening

• A file must be opened before reading from or writing to it.
• ofstream or fstream objects can be used to open a file for writing, while ifstream objects are used for reading.
• A file can be opened in different modes for read and write operations.

File Management

• External mass storage media, such as hard disks, are block-oriented, transferring data in blocks of 512 bytes or multiples thereof.
• Efficient file management involves storing data in a temporary storage in main memory, known as a file buffer.
• A file is simply a long byte array from the viewpoint of a C++ program.
• Each character in a file occupies a byte position, with the first byte at position 0.

File Access

• The current file position is the position of the byte that will be read or written next.
• Each byte transferred automatically increases the current file position by 1.
• In sequential access, data is read or written byte by byte in a fixed order.
• Write operations can create a new file, overwrite an existing file, or append new data to an existing file.
• Easy access to given data in a file requires setting the current file position as required.

Streams and Files

• Files are a means to store data in a storage device.
• C++ file handling provides a mechanism to store output of a program in a file and read from a file on the disk.
• Streams refer to a sequence of bytes.
• Files store data.

Learn about the concept of File IO, the transfer of data between secondary memory and main memory, as well as the differences between text and binary files in terms of readability and data representation. Classes istream and ostream are involved in the process.