Copying a symbolic link in Python
Just do
def copy(src, dst): if os.path.islink(src): linkto = os.readlink(src) os.symlink(linkto, dst) else: shutil.copy(src,dst)
shutil.copytree does something similar, but as senderle noted, it's picky about copying only directories, not single files.
Python 3 follow_symlinks
In Python 3, most copy methods of shutil
have learned the follow_symlinks
argument, which preserves symlinks if selected.
E.g. for shutil.copy
:
shutil.copy(src, dest, follow_symlinks=False)
and the docs say:
shutil.copy(src, dst, *, follow_symlinks=True)
Copies the file src to the file or directory dst. src and dst should be strings. If dst specifies a directory, the file will be copied into dst using the base filename from src. Returns the path to the newly created file.
If
follow_symlinks
is false, and src is a symbolic link, dst will be created as a symbolic link. If follow_symlinks` is true and src is a symbolic link, dst will be a copy of the file src refers to.
This has one problem however: if you try to overwrite an existing file or symlink, it fails with:
FileExistsError: [Errno 17] File exists: 'b' -> 'c'
unlike the follow_symlinks=True
which successfully overwrites.
The same also happens for os.symlink
, so I ended up using instead:
#!/usr/bin/env python3import shutilimport osdef copy(src, dst): if os.path.islink(src): if os.path.lexists(dst): os.unlink(dst) linkto = os.readlink(src) os.symlink(linkto, dst) else: shutil.copy(src, dst)if __name__ == '__main__': os.symlink('c', 'b') os.symlink('b', 'a') copy('a', 'b') with open('c', 'w') as f: f.write('a') with open('d', 'w'): pass copy('c', 'd') copy('a', 'c')
Tested in Ubuntu 18.10, Python 3.6.7.