12.1 Print the name of the OS
import os def main(): # Print the name of the OS print os.name; if __name__ == "__main__": main()
12.2 Check for item existence and type
N.B. textfile.txt must exist for the following...
import os from os import path def main(): # Check for item existence and type print "Item exists: " + str(path.exists("textfile.txt")) print "Item is a file: " + str(path.isfile("textfile.txt")) print "Item is a directory: " + str(path.isdir("textfile.txt")) if __name__ == "__main__": main()
The path
class has several methods which take a file as an argument and return information about the file.
12.3 Work with file paths
import os from os import path def main(): # Work with file paths print "Item's path: " + str(path.realpath("textfile.txt")) print "Item's path and name: " + str(path.split(path.realpath("textfile.txt"))) if __name__ == "__main__": main()
Call .realpath("textfile.txt")
to get the file path
Call .split()
on theoutput of .realpath()
to get an array consisting of the "item's path" and the "filename". So, the filename is "split" off of the path and you get them separately, that's handy...
This path output is run through the string method str()
of Python so it can be concatenated with other string text.
12.4 Get the modification time
from os import path import datetime from datetime import time import time def main(): # Get the modification time modtime = time.ctime(path.getmtime("textfile.txt")) print modtime # Get it as a datetime format instead of a ctime format print datetime.datetime.fromtimestamp(path.getmtime("textfile.txt")) if __name__ == "__main__": main()
Call path.getmtime("textfile.txt")
on the path to the file
The time class's ctime method time.ctime()
is used to convert the output into a readable time.
12.5 Calculate how long ago the item was modified
from os import path import datetime from datetime import date, time import time def main(): # Calculate how long ago the item was modified timediff = datetime.datetime.now( ) - datetime.datetime.fromtimestamp(path.getmtime("textfile.txt")) print "It has been " + str(timediff) + " minutes since the file was modified" print "Or, " + str(timediff.total_seconds()) + " seconds" if __name__ == "__main__": main()