[Samba] File growth behavior of Mac OS X and WinXP

[Victor Moran]

Hello List,

I've searched the internet and I haven't been able to figure this out.
I hope someone here can point me in the right direction.

I have a MacOSX 10.3 machine and a WinXP machine that are being used to
produce large video clips (@1gig).  After they are rendered and ready
for playback, they are copied to the playout machines using a system
that uses watch folders shared out over samba.

The watch folder works based on file size.  For example, 40 seconds
after a file's filesize stops growing, the system assumes the file is
complete and starts moving the file onto the playout device.

The problem I've found is that windows xp and mac osx (10.3 at least)
both cause samba to allocate the entire file size at the start of the
transfer.  For large files this causes a problem since the file is not
finished writing to the smb share when the playout transfer system
takes the file and tries to move it and then delete it.

Any help on how to change OSX and WinXP's behavior or how to keep samba
from allocating disk space at the start of a write would be very
appreciated.

Thanks,
Victor.