Ok then keep the things as it is a better idea right? Thanks Anoop > -----Original Message----- > From: Jeff Layton [mailto:jlayton@xxxxxxxxxx] > Sent: Thursday, May 21, 2009 5:30 PM > To: Anoop P.A. > Cc: linux-nfs@xxxxxxxxxxxxxxx > Subject: Re: NFS-CIFS locking > > On Thu, 21 May 2009 00:23:30 -0700 > "Anoop P.A." <Anoop_P.A@xxxxxxxxxxxxxx> wrote: > > > That's true. But consider following conditions, > > > > 1. Copy one "1 GB" file to nfs share using command "cp". While cp is > > progressing try deleting that file from CIFS share. > > > > 2. Copy one "1 GB" file to CIFS share using "Drag n Drop". While copy is > > progressing try deleting that file from NFS share > > > > What I would expect in these scenarios is "user should not be able to > > delete the file under copying". > > > > I'm afraid that expectation is wrong, at least on unix. > > > I assume linux "cp" implementation will not lock a file under copying > > (At least I didn't see any fcntl / flock calls on tracing cp). > > > > With few exceptions, locks under unix are advisory. They're sort of > like stoplights -- they only work if everyone is paying attention to > them. > > > So I assume this is quite normal in Linux environment (file in use at > > one place can be deleted from another shell). But in a mixed environment > > windows client will expect an open file to be protected from being > > deleted. > > > > Is it possible to achieve this?. > > > > Not really, no. On unix in general, it's completely legitimate and > common to remove a file that's open. What will happen is that the > filename will be removed from the namespace. It won't show up in > directory listings, and isn't reachable by apps that didn't already > have it open. Its blocks will still exist on disk however and > applications that have it open will still be able to work with the > filehandle normally. Eventually when the last close happens on the file > it will be "deleted". > > The fact that windows does not do this has more to do with the way that > its local filesystems are designed. It's also an endless source of > headache for administrators. For instance, backup programs on windows > often cause real problems for running applications that try to delete > or rename files while in the middle of being backed up. > > -- > Jeff Layton <jlayton@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
