#!/usr/bin/env python3 import sys import os # Simulate the behavior of the ls program # Allow the user to specify a directory to list the contents of if __name__ == '__main__': path = '.' # Handle arguments if len(sys.argv) > 1: # The path should be the only argument not starting with a - for a in sys.argv[1:]: if not a.startswith('-'): path = a # If the directory does not exist quit if not os.path.isdir(path): print('Directory does not exist.') exit() # Break since we should have found the path break # use list comprehension to ignore files begining with . files = [f for f in os.listdir(path)] # Sort our files in ascending order files.sort() # Decide on print -l behavior # print(' '.join(files)) # We have string.startswith and .endswith methods [print(f) for f in files if not f.startswith('.')]