In this post, we’ll discuss how to copy a file in Python with code examples.
How to copy a file in Python?
shutil
has many methods you can use. One of which is:
from shutil import copyfile
copyfile(src, dst)
# 2nd option
copy(src, dst) # dst can be a folder; use copy2() to preserve timestamp
- Copy the contents of the file named
src
to a file nameddst
. Bothsrc
anddst
need to be the entire filename of the files, including path. - The destination location must be writable; otherwise, an
IOError
exception will be raised. - If
dst
already exists, it will be replaced. - Special files such as character or block devices and pipes cannot be copied with this function.
- With
copy
,src
anddst
are path names given asstr
s.
Another shutil
method to look at is shutil.copy2()
. It’s similar but preserves more metadata (e.g. time stamps).
If you use os.path
operations, use copy
rather than copyfile
. copyfile
will only accept strings.
copy2(src,dst)
is often more useful than copyfile(src,dst)
because:
- it allows
dst
to be a directory (instead of the complete target filename), in which case the basename ofsrc
is used for creating the new file; - it preserves the original modification and access info (mtime and atime) in the file metadata (however, this comes with a slight overhead).
Here is a short example:
import shutil
shutil.copy2('/src/dir/file.ext', '/dst/dir/newname.ext') # complete target filename given
shutil.copy2('/src/file.ext', '/dst/dir') # target filename is /dst/dir/file.ext
Copying files in Python
In Python, you can copy the files using
shutil
moduleos
modulesubprocess
module
import os
import shutil
import subprocess
1) Copying files using shutil module
shutil.copyfile
signature
shutil.copyfile(src_file, dest_file, *, follow_symlinks=True)
# example
shutil.copyfile('source.txt', 'destination.txt')
shutil.copy
signature
shutil.copy(src_file, dest_file, *, follow_symlinks=True)
# example
shutil.copy('source.txt', 'destination.txt')
shutil.copy2
signature
shutil.copy2(src_file, dest_file, *, follow_symlinks=True)
# example
shutil.copy2('source.txt', 'destination.txt')
shutil.copyfileobj
signature
shutil.copyfileobj(src_file_object, dest_file_object[, length])
# example
file_src = 'source.txt'
f_src = open(file_src, 'rb')
file_dest = 'destination.txt'
f_dest = open(file_dest, 'wb')
shutil.copyfileobj(f_src, f_dest)
2) Copying files using os module
os.popen
signature
os.popen(cmd[, mode[, bufsize]])
# example
# In Unix/Linux
os.popen('cp source.txt destination.txt')
# In Windows
os.popen('copy source.txt destination.txt')
os.system
signature
os.system(command)
# In Linux/Unix
os.system('cp source.txt destination.txt')
# In Windows
os.system('copy source.txt destination.txt')
3) Copying files using subprocess module
subprocess.call
signature
subprocess.call(args, *, stdin=None, stdout=None, stderr=None, shell=False)
# example (WARNING: setting `shell=True` might be a security-risk)
# In Linux/Unix
status = subprocess.call('cp source.txt destination.txt', shell=True)
# In Windows
status = subprocess.call('copy source.txt destination.txt', shell=True)
subprocess.check_output
signature
subprocess.check_output(args, *, stdin=None, stderr=None, shell=False, universal_newlines=False)
# example (WARNING: setting `shell=True` might be a security-risk)
# In Linux/Unix
status = subprocess.check_output('cp source.txt destination.txt', shell=True)
# In Windows
status = subprocess.check_output('copy source.txt destination.txt', shell=True)
The table below summarises the capabilities of each of the methods discussed in this article. Note that the only method that accepts File Objects is shutil.copyfileobj
.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Function preserves supports accepts copies other permissions directory dest. file obj metadata ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― shutil.copy ✔ ✔ ☐ ☐ shutil.copy2 ✔ ✔ ☐ ✔ shutil.copyfile ☐ ☐ ☐ ☐ shutil.copyfileobj ☐ ☐ ✔ ☐ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Example Answer #3:
Copying a file is a relatively straightforward operation as shown by the examples below, but you should instead use the shutil stdlib module for that.
def copyfileobj_example(source, dest, buffer_size=1024*1024):
"""
Copy a file from source to dest. source and dest
must be file-like objects, i.e. any object with a read or
write method, like for example StringIO.
"""
while True:
copy_buffer = source.read(buffer_size)
if not copy_buffer:
break
dest.write(copy_buffer)
If you want to copy by filename you could do something like this:
def copyfile_example(source, dest):
# Beware, this example does not handle any edge cases!
with open(source, 'rb') as src, open(dest, 'wb') as dst:
copyfileobj_example(src, dst)
Hope you learned something from this post.
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