How to Check if a File is Open or Closed in Python

To determine if a file is open or closed in Python, you can use the closed attribute.

filename.closed

The closed attribute returns a boolean value:

• True if the file is closed
• False if the file is open for reading, writing, or appending

Why is this important? This information is crucial as it helps prevent errors when performing read or write operations on a file that is already closed or not yet opened.

Example

Let's open a file for reading:

>>> f = open('example.txt', 'r')

Now, use the closed attribute to check if the file is open or closed:

>>> f.closed

This returns False because the file is open.

False

It doesn’t matter whether the file is open for reading or writing, just that it is open.

If the file were closed, the closed attribute would return True.

How can you tell if the file is open for reading or writing? Once you've confirmed that the file is open (f.closed == False), you can determine if it is open for reading or writing using the mode attribute.