Paste file in new file in python

Question

Is there a way to just open/create filehandle = open( "example.bin", "wb") and extend this file with an existing file?

I think about something like the .extend from function for lists Like so:

filehandle = open( "example.bin", "wb")
filehande.extend(existing_file.bin)

I know that i can read the existing file and write that to a variable/list and "paste" it in the new file but im curious if there is an easier option like this...

I know, if you read my question twice im asking about a similar method. — Nico, Oct 11 '17 at 07:07
@cᴏʟᴅsᴘᴇᴇᴅ Thats possible but No option for me. — Nico, Oct 11 '17 at 07:12
@cᴏʟᴅsᴘᴇᴇᴅ nope but i Want to solve it in Python — Nico, Oct 11 '17 at 07:14
Using [`pathlib`](https://docs.python.org/3/library/pathlib.html) you can do stuff like this: `from pathlib import Path; p1, p2 = Path('path1'), Path('path2'); p1.write_bytes(p1.read_bytes() + p2.read_bytes())` which appends the contents of 'path2' to 'path1'. — PM 2Ring, Oct 11 '17 at 07:33

blakev · Accepted Answer · 2017-10-11T07:16:50.520

2

with open('original', 'a') as out_file, open('other', 'r') as ins_file:
    out_file.write(ins_file.read())

This will append the contents of other onto original. If you're dealing with binary data you can change the mode on each to ab and rb.

If the contents of the file are large you can do it in chunks too.

edited Oct 11 '17 at 07:16

answered Oct 11 '17 at 07:06

blakev

4,154
2
32
52

1

This will actually __replace__ the content of `original` with `other`. Opening an existing file a in write ("w") mode immediatly erases the file's content. To append to an existing file you want to open in append ("a") mode, obviously. – bruno desthuilliers Oct 11 '17 at 07:14

score 1 · Answer 2 · answered Oct 11 '17 at 07:17

You can't merge file objects. You can make a list of each file and extended them

files_combined = list(open("example.bin", "wb")) + list(open("file_2"))

Will return a list with all the lines in file_2 appended to file_1, but in a new list. You can then save it to a new file, or overwrite one of the files.

Paste file in new file in python

2 Answers2