How to copy file object in python

Question

I am opening a file in python using with command as given below. Then I am copying the object to w.

import os

os.chdir(r"C:\Users\")

with open(r"abc.040", 'r+') as k:
    w = k

for a in w:
    print(a)

But when I try to iterate w object through for loop, I am getting below error.

Traceback (most recent call last):
  File "C:/Users/w.py", line 8, in <module>
    for a in w:
ValueError: I/O operation on closed file.

How to copy a file instance

Unlike some other languages Python creates references by = and no copies. So you are still using the same object just under a new name. — Klaus D.
– Klaus D., Commented Aug 7, 2018 at 7:31
When you open a file in a with block, the file gets automatically closed when you exit the block. k (and w, they are just two names for the same file object) is closed when you reach the for loop. — Thierry Lathuille
– Thierry Lathuille, Commented Aug 7, 2018 at 7:32

Rakesh · Accepted Answer · 2018-08-07 07:28:00Z

1

Use readlines

Ex:

import os

os.chdir(r"C:\Users")
with open(r"abc.040", 'r+') as k:
    w = k.readlines()

for a in w:
    print(a)

answered Aug 7, 2018 at 7:28

Rakesh

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2 Comments

Is it not possible to copy the object and use it. Something like deepcopy

file content is copied to w using 'readlines' for you to reuse.