Modifying a symlink in python

Question

How do I change a symlink to point from one file to another in Python?

The os.symlink function only seems to work to create new symlinks.

Answer 1

If you need an atomic modification, unlinking won't work.

A better solution would be to create a new temporary symlink, and then rename it over the existing one:

os.symlink(target, tmpLink) os.rename(tmpLink, linkName) 

You can check to make sure it was updated correctly too:

if os.path.realpath(linkName) == target:     # Symlink was updated 

According to the documentation for os.rename though, there may be no way to atomically change a symlink in Windows. In that case, you would just delete and re-create.

Answer 2

A little function for Python2 which tries to symlink and if it fails because of an existing file, it removes it and links again. Check [Tom Hale's answer] for a up-to-date solution.

import os, errno  def symlink_force(target, link_name):     try:         os.symlink(target, link_name)     except OSError, e:         if e.errno == errno.EEXIST:             os.remove(link_name)             os.symlink(target, link_name)         else:             raise e 

For python3 except condition should be except OSError as e:
[Tom Hale's answer]: https://stackoverflow.com/a/55742015/825924