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I am trying to copy files on Windows with Python 2.7, but sometimes this fails.

shutil.copyfile(copy_file, dest_file)

I get the following IOError:

[Errno 2] No such file or directory

But the file does exist! The problem is that the path of the file is too long. (> 255 characters)

How do I copy these files? It isn't a problem to open them in other applications.

To create a file with a too long path, create a file with an as long as possible file name and move the containing folder deeper down a tree structure.

I've been trying some of these methods without success: http://timgolden.me.uk/python/win32_how_do_i/copy-a-file.html

Gfy
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    Try changing your working directory into the directory containing the file (moving one directory deeper at a time if necessary), then in `shutil.copyfile` use a relative path rather than the full path. – mpen Dec 28 '12 at 20:39

3 Answers3

35

I wasn't sure about the 255 char limit so I stumbled on this post. There I found a working answer: adding \\?\ before the path.

shutil.copyfile("\\\\?\\" + copy_file, dest_file)

edit: I've found that working with long paths causes issues on Windows. Another trick I use is to just shorten the paths:

import win32api
path = win32api.GetShortPathName(path)
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Gfy
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8

Thanks for the answer Gfy. I have a requirement to use relative paths. The \\?\ can't be added successfully to a relative path, so it's necessary to convert to an absolute path first (run from desktop):

import os

def clean_path(path):
    path = path.replace('/',os.sep).replace('\\',os.sep)
    if os.sep == '\\' and '\\\\?\\' not in path:
        # fix for Windows 260 char limit
        relative_levels = len([directory for directory in path.split(os.sep) if directory == '..'])
        cwd = [directory for directory in os.getcwd().split(os.sep)] if ':' not in path else []
        path = '\\\\?\\' + os.sep.join(cwd[:len(cwd)-relative_levels]\
                         + [directory for directory in path.split(os.sep) if directory!=''][relative_levels:])
    return path

clean_path('samples')
\\?\C:\Users\Username\Desktop\samples
clean_path('\samples')
\\?\C:\Users\Username\Desktop\samples
clean_path('..\samples')
\\?\C:\Users\Username\samples
clean_path('..\..\samples')
\\?\C:\Users\samples
clean_path('C:\Users\Username\Dropbox')
\\?\C:\Users\Username\Dropbox
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Hywel Thomas
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0

Maybe do something like this:

path = "some/really/really/long/path/more/than/255/chars.txt"

def copyFile(path, dest, relative=0):
    if len(path) > 255:
        if not os.sep in path:
            raise SomeException()
        moveTo, path = path.split(os.sep, 1)
        os.chdir(moveTo)
        copyFile(path, dest, relative + 1)
    else:
        path_base = ['..'] * relative
        path_rel = path_base + [dest]
        shutil.copyfile(path, os.path.join(*path_rel))

This is tested, and does work... however, if the destination is more than 255 chars, you would be back in the same boat. In that case, you may have to move the file several times.

sberry
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  • I get the following error: WindowsError: [Error 2] Het systeem kan het opgegeven bestand niet vinden: 'copy' (system can't find file) and 'copy' is a folder in my path. I've been trying with relative paths, but I can't get it to work. Changing the working dir and trying os.path.exists() on the long file name results in False. My destination dir is close to 255, but still enough below that. – Gfy Dec 28 '12 at 21:26