[rdiff-backup-users] Workaround for "Exception ''module' object has no attribute 'symlink''" on Windows

[Paul Laferriere]

While doing a local backup on Windows 7, source and destination both 
NTFS, I was getting getting this error:

Exception ''module' object has no attribute 'symlink'' raised of class 
'<type
'exceptions.AttributeE
rror'>':
  File "rdiff_backup\robust.pyc", line 32, in check_common_error
  File "rdiff_backup\rpath.pyc", line 111, in copy
  File "rdiff_backup\rpath.pyc", line 1002, in symlink

Exception ''module' object has no attribute 'symlink'' raised of class 
'<type
'exceptions.AttributeE
rror'>':
  File "rdiff_backup\Main.pyc", line 304, in error_check_Main
  File "rdiff_backup\Main.pyc", line 324, in Main
  File "rdiff_backup\Main.pyc", line 280, in take_action
  File "rdiff_backup\Main.pyc", line 346, in Backup
  File "rdiff_backup\backup.pyc", line 38, in Mirror
  File "rdiff_backup\backup.pyc", line 232, in patch
  File "rdiff_backup\rorpiter.pyc", line 281, in __call__
  File "rdiff_backup\backup.pyc", line 529, in fast_process
  File "rdiff_backup\backup.pyc", line 553, in patch_to_temp
  File "rdiff_backup\backup.pyc", line 577, in patch_snapshot_to_temp
  File "rdiff_backup\backup.pyc", line 617, in write_special
  File "rdiff_backup\robust.pyc", line 32, in check_common_error
  File "rdiff_backup\rpath.pyc", line 111, in copy
  File "rdiff_backup\rpath.pyc", line 1002, in symlink

Traceback (most recent call last):
  File "rdiff-backup", line 30, in <module>
  File "rdiff_backup\Main.pyc", line 304, in error_check_Main
  File "rdiff_backup\Main.pyc", line 324, in Main
  File "rdiff_backup\Main.pyc", line 280, in take_action
  File "rdiff_backup\Main.pyc", line 346, in Backup
  File "rdiff_backup\backup.pyc", line 38, in Mirror
  File "rdiff_backup\backup.pyc", line 232, in patch
  File "rdiff_backup\rorpiter.pyc", line 281, in __call__
  File "rdiff_backup\backup.pyc", line 529, in fast_process
  File "rdiff_backup\backup.pyc", line 553, in patch_to_temp
  File "rdiff_backup\backup.pyc", line 577, in patch_snapshot_to_temp
  File "rdiff_backup\backup.pyc", line 617, in write_special
  File "rdiff_backup\robust.pyc", line 32, in check_common_error
  File "rdiff_backup\rpath.pyc", line 111, in copy
  File "rdiff_backup\rpath.pyc", line 1002, in symlink
AttributeError: 'module' object has no attribute 'symlink'

which was reported here: 
http://lists.nongnu.org/archive/html/rdiff-backup-users/2009-10/msg00010.html

Adding --exclude-symbolic-links solved the problem.  This option should 
be redundant on Windows, but apparently isn't.