Python Tutorial: OS Module - Use Underlying Operating System Functionality

The OS module allows us to interact wiht the underlying operating system in several different ways. - Navigate the file system - Get file information - Look up and change the environment variables - Move files around - Many more To begin, import the os module. This is a built in module, no third party modules need to be installed. # Get current working directory os.getcwd() # Change directory, this requires a path to change to os.chdir(path) # List directory, you can pass a path, but by default it is in the current directory os.listdir() # Multiple options for creating directories mkdir() # Use for making one directory makedirs(). # Use if you want to create multiple directories at once # Remove directories rmdir(file). # Recommended use case removedirs(file) # Removes intermediate directories if specified # Rename a file or folder os.rename(‘test.txt’, ‘demo.txt’). # This renames text.txt to demo.txt # Look at info about files os.stat(test.txt) # Useful stat results: st_size (bytes), st_mtime (time stamp) # To see entire directory tree and files within # os.walk is a generator that yields a tuple of 3 values as it walks the directory tree for dirpath, dirnames, filenames in os.walk(routepath): print(‘Current Path:’, dirpath) print(‘Directories:’, dirnames) print(‘Files:’, filenames) print() # This is useful for locating a file that you can’t remember where it was # If you had a web app, and you wanted to keep track of the file info within a certain directory structure, then you could to thru the os.walk method and go thru all files and folders and collect file information. # Access home directory location by grabbing home environment variable os.environ.get(‘HOME’). # Returns a path # To properly join two files together use os.path.join() file_path = os.path.join(os.environ.get(‘HOME’), ‘test.txt’) # the benefit of os.path.join, is it takes the guess work out of inserting a slash # os.path has other useful methods os.path.basename # This will grab filename of any path we are working on os.path.dirname(‘/tmp/test.txt’) # returns the directory /tmp os.path.split(‘/tmp/test.txt’) # returns both the directory and the file as a tuple os.path.exists(‘/tmp/test.txt’) # returns a boolean os.path.isdir(‘/tmp/test.txt’) # returns False os.path.isfile(‘/tmp/test.txt’) # returns True os.path.splitext(‘/tmp/test.txt’) # Splits file route of the path and the extension # returns (‘/tmp/test’, ‘.txt’) # This is alot easier than parsing out the extension. Splitting off and taking the first value is much better. # Very useful for file manipulation