27-os-module.md

Python os module

Video link: https://youtu.be/vNP15Wov7sQ

In this video, we learned to use the os module to perform various directory operations like creating, renaming, and removing directories with the help of examples.

Programs in the Video

• Getting Current Directory
• Changing Directory
• Listing all Directories and Files
• Making a New Directory
• Renaming a Directory or a File
• Removing Directory or File

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Getting Current Directory

We use the getcwd() function of the os module to get the path to the current directory.

import os

current_dir = os.getcwd()
print(current_dir)

When you run the code, the current working directory that is the directory containing our Python file is printed.

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Changing Directory

In Python, we can change the current working directory by using the chdir() function of the os module.

As we saw previously, the present working directory is the directory containing our Python file. Let's change the current working directory

import os

current_dir = os.getcwd()
print(current_dir)

os.chdir("/path/new/location")
print(os.getcwd())

Output

<your file directory location>
<new location>

Note: Now if we create a file inside the current directory, our file will be created inside <new location>.

import os

current_dir = os.getcwd()
print(current_dir)

os.chdir("<new location>")

with open("test.txt", "w") as f:
    f.write("This is a test file.")

We can see the test.txt file is created inside the current working directory which is <new location>.

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Listing all Directories and Files

In Python, all files and sub-directories inside a directory can be retrieved using the listdir() function of the os module.

For example,

import os

print(os.listdir())

This function returns a list containing all files and sub-directories in the current working directory.

We can also pass an optional path argument to listdir() to return files and sub-directories from a specific path.

import os

print(os.listdir("<path>"))

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Making a New Directory

We can create a new directory using the mkdir() function of the os module.

import os

os.mkdir("test")

This creates a new test directory in our current directory.

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Renaming a Directory or a File

We can rename any directory or file using the os.rename() function which takes in 2 arguments: old name and new name.

import os

# rename directory or file
os.rename('<old_name>', '<new_name>')

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Removing Directory or File

We can remove a file using the remove() function of the os module.

import os

print(os.listdir())

os.remove("<filename>")

print(os.listdir())

After running this code, the file is deleted, so the second os.listdir() will not list the file.

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To remove a directory, we use the rmdir() function.

import os

print(os.listdir())

os.rmdir("<path_to_directory>")

print(os.listdir())

Note: One thing we need to remember when removing a directory is that the directory must be empty. Otherwise, an exception will be raised.