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understanding os.path.join in Python

The os.path.join() method is a versatile tool that can be used in several ways. In this blog post, we will look at 5 examples of how to use the os.path.join() method in Python.

We will start with a basic example of how to join two paths together, and then move on to more complex examples that involve combining multiple paths and file names. Let’s get started!

os.path.join Syntax in Python

os.path.join(path, *paths)


  •  path: A path-like object representing a file system path.
  • *path: A path-like object representing a file system path. It represents the path components to be joined.


Return Value

The os.path.join() method returns a string that represents the concatenated path components.

Example 1: Joining Two Paths Together

The os.path.join() method can be used to join two paths together into a single string. The following code will create a new path that is the combination of “/home” and “howtouselinux”:

print(os.path.join("/home", "howotouselinux"))

Example 2: Combining Multiple Paths and File Names

The os.path.join() method can also be used to combine multiple paths and file names into a single string. The following code will create a new path that is the combination of “/home”, “howtouselinux”, and “test.txt”:

print(os.path.join("/home", "howotouselinux","test.txt"))
print(os.path.join("/home", "howotouselinux/test","test.txt"))

Example 3: Combining Multiple Paths and absolute path

If a path component represents an absolute path, then all previous components joined are discarded and joining continues from the absolute path component.

>>> print(os.path.join("/home", "howotouselinux","/test.txt"))

Example 4: Combining Multiple Paths and “”

If the last path component to be joined is empty then a directory separator (‘/’) is put at the end.

>>> print(os.path.join("/home", "howotouselinux",""))

Example 5: os.path.join + os.path.split

>>> p = os.path.join(os.getcwd(), 'foo.txt')
>>> p
>>> os.path.dirname(p)
>>> os.path.basename(p)
>>> os.path.split(os.getcwd())
('/Users/howtouselinux', 'tmp')
>>> os.path.splitext(os.path.basename(p))
('foo', '.txt')

Best practice for Python OS Path Join Method

  • Always use os.path.join() to join paths instead of manually concatenating strings. It ensures compatibility across different operating systems by using the appropriate separator (/ or \).
  • Employ predefined constants like os.sep or os.path.sep for directory separators to enhance code readability and portability.
  • For more complex file path manipulations, consider using the pathlib module, which provides an object-oriented interface and is more expressive and powerful than os.path.


Understanding os.path in Python

The os.path module in Python provides functions for common pathname manipulations.

It’s useful for working with file paths and directory names, allowing you to handle paths across different operating systems without worrying about the underlying platform-specific differences.

Path Manipulation Functions:

  • os.path.join(): Combines one or more path components intelligently based on the operating system.
  • os.path.basename(): Extracts the filename from a path.
  • os.path.dirname(): Retrieves the directory name from a path.
  • os.path.splitext(): Splits a path into its root and extension.

Path Information:

  • os.path.exists(): Checks if a path exists.
  • os.path.isfile(): Determines if a path points to a file.
  • os.path.isdir(): Checks if a path is a directory.

Path Properties:

  • os.path.getsize(): Retrieves the size of a file in bytes.
  • os.path.getctime(), os.path.getmtime(), os.path.getatime(): Get the creation, modification, or access time of a file.
  • os.path.isabs(): Checks if a path is absolute.

Path Operations:

  • os.path.abspath(): Returns the absolute path of a file or directory.
  • os.path.normpath(): Normalizes a path by removing double slashes and symbolic links.
  • os.path.relpath(): Computes a relative path between two paths.

Platform Independence:

  • os.path.sep: Returns the path separator specific to the current platform (‘/’ on Unix/Linux, ‘\\’ on Windows).
  • Note: These functions handle path separators appropriately based on the operating system.

The os.path module is versatile, making it easy to work with paths, whether you’re dealing with files, directories, or path strings. It’s a crucial part of file and directory operations in Python.

understanding the os Module in Python

The os module in Python provides a way to interact with the operating system, enabling various system-related functionalities.

File and Directory Operations:

  • os.listdir(): Retrieves the contents of a directory.
  • os.mkdir() and os.makedirs(): Create directories.
  • os.remove() and os.rmdir(): Delete files and directories, respectively.
  • os.rename(): Renames a file or directory.

Path Manipulation:

  • os.path.join(): Concatenates multiple path components using the appropriate separator based on the operating system.
  • os.path.exists(): Checks if a path exists.
  • os.path.abspath(): Returns the absolute path of a file or directory.

Operating System Information:

  • Provides the name of the operating system (‘posix’ for Unix/Linux, ‘nt’ for Windows).
  • os.environ: Accesses environment variables.
  • os.getlogin(): Returns the username of the currently logged-in user.

Process Control:

  • os.system(): Executes a shell command.
  • os.spawn*(): Functions for process creation.
  • os.kill(): Sends a signal to a process.

File Permissions:

  • os.chmod(): Changes the permissions of a file.
  • os.chown(): Changes the owner and group ID of a file.


  • os.getpid(): Returns the current process ID.
  • os.getcwd(): Gets the current working directory.
  • os.pathsep: Platform-specific path separator (‘:’ on Unix/Linux, ‘;’ on Windows).

The os module provides an interface for basic operating system interactions, but for more advanced file and path manipulations, the pathlib module is recommended, offering an object-oriented approach to file system paths.