Revision Guide: File Handling in Python

A file is a named location on secondary storage for permanent data storage.

Files can be text (human-readable) or binary (non-human readable).

Text files store data as ASCII characters using extensions like .txt, .csv.

Binary files store data as bytes, such as images, and require specific software.

Use `open(file_name, access_mode)` to open a file and obtain a file object.

Modes include 'r' (read), 'w' (write), 'a' (append), and their binary counterparts.

Always close files using `file_object.close()` to free resources after operations.

The 'with' statement auto-closes files after exiting its block, simplifying file management.

Use `write(string)` for single strings and `writelines(list)` for multiple strings.

Use `read(n)` for bytes, `readline()` for a single line, and `readlines()` for all lines.

The `tell()` method returns the current file pointer position in bytes.

Use `seek(offset, reference)` to move the file pointer within the file.

To traverse a file, open it in read mode and iterate using loops.

Used for serializing Python objects to binary files using `dump()` and `load()`.

Pickling converts Python objects to a byte stream for storage or transmission.

Unpickling is restoring a pickled byte stream back to a Python object.

Use try-except blocks to handle exceptions during file operations effectively.

EOF is reached when there is no more data to read; useful for loops.

Data is written to a file buffer; flush it before closing to prevent data loss.

Buffered I/O saves data in memory before writing to disk, improving performance.