Re: [rdiff-backup-users] win32 success! and one little problem :)

[David Kempe]

Greg Freemyer wrote:
> Great work.  I assume you are saying that you have a pure win32 version
> working.  ie. No use of the cygwin dll.

sorry Greg, I just couldn't get that to work.
the c files for rdiff-backup gave me the same errors that I posted with 
mingw32 with Visual Studio 6. Looks like they only compile with gcc from 
cygwin or linux. and I tried your suggestion of compiling them with the 
gcc from cygwin with the right flags, it (the .o file) compiles with 
warnings, but then gives heaps more erros when you go onto the .dll.
So I gave up on that and worked on paring back the cygwin version to as 
small as possible. this is merely a result of that. sorry, I'm not that 
brilliant at c to make it work :(


> That is great.
not as great as you thought :)

> A couple questions:
>
> Are you using a native win32 /bin/sh, or a cygwin one?
cygwin /bin/sh.exe


> What python are you using (win32 or cygwin)?

cywin.

> Do you need the cygwin.dll installed at all on the installation
> computer?

yes, but my setup.exe looks after that, and there should be no conflicts 
with existing setups (except for the outlined /bin/sh problem) as its 
all stored in its own self contained folder.

> What is the status of backing up:
>    Large files (over 2 GB used to be a problem in cygwin)

I haven't tested - would you like a copy to test? (mail me off list and 
I will send you a link.) I haven't included any documentation or 
licensing yet as its still in development, so I am reluctant to release 
it to the world without at least a copy of the GPL :)

>    ACLs  (Access Control Lists)

according to http://pylibacl.sourceforge.net/ the pylibacl module 
doesn't support cygwin.
previously when I was using cygwin ssh and not plink I had a problem 
where if your cygwin install didn't pick up on the permissions properly, 
ssh couldn't determine the owner of the ssh keys and refused to use 
them. On a FAT32 partition this was pretty impossible to get around. It 
is possible with a cygwin variable, but that didn't work as we have a 
Samba domain controller, which didn't mix well with it. So strangely 
enough I have to use plink because of samba :)

Anyway, pylibacl support aside, I think that ACL/permission support in 
cygwin is dodgy enough as to be a problem for many people. rdiff-backup 
would need a native win32 acl module I would have thought.

>    Open files  (Most commercial packages use Open File Manager from St.
> Bernard to make this work.  It can be configured for random backup
> programs, but I have never tried to configure it before.) 

I did ask them. Basically, OFM works by detecting an SMB using accessing 
shares, then provides something very similar to the WIN2K3 shadow copy 
to that user. At around AU$900 for a license, its not something I am 
going to go for - stopping the services is easy enough and I don't know 
a client that can't afford to not have exchange/mssql stopped for an 
hour or so each night. You might be different. Alternatively, both those 
programs have backup/deleted items retaining setups, so you can get 
around it that way.
for exchange I just set the deleted items retention to 30days and stop 
the service and back it up. rdiff-backup can't do diffs on the database, 
so you can't do it very often unless you have a large disk (I use 
firewire).
MSSQL can be configured to do dumps of its database pretty often, so you 
can back up the dumps with rdiff-backup.

As for other abitrary files, there is no reason why OFM wouldn't work, 
but it just relies on that smb user login method to tell when to offer 
the open files.


> Congratulations on your success.  I tried a get pure win32 version about
> a year ago and gave up, so I know it was not a trivial effort.

A pure win32 version would that some rewriting of rdiff-backup I am not 
prepared to undertake. Especially since the cygwin version just has the 
same license and the installer is only 2.3meg.


> BTW: it would be great if you could put the above info on the wiki.

I'll try get to that this afternoon :)

dave