#!/usr/bin/env python 3.5
import sys, os

def write_to_file(src):
    try:
        with open(src, "a") as f:
            user_input = input("Write to file: ")
            f.write(user_input)
    except IOError as e:
        print(e)

args = sys.argv
if len(args) == 2:
    src = args[1]
    size_before = os.stat(src)
    print("Current file size: ",size_before.st_size, "bytes")
    write_to_file(src)
    size_after = os.stat(src)
    print("Current file size: ",size_after.st_size, "bytes")
else:
    print("Usage: ./lab2.py \\path-to-file")