[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: using new versions of emacs without stoping a session
From: |
Stefan Monnier |
Subject: |
Re: using new versions of emacs without stoping a session |
Date: |
Thu, 18 Apr 2019 09:56:03 -0400 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) |
> The difference between the systems is on the filesystem level: by
> default Windows doesn't allow to unlink file's data from its directory
> entry, if some application has that file open, while most Unix
> filesystems by default do allow that. I don't know why Windows'
> default is what it is.
My guess would be that it's linked to the FAT file-system where there is
no notion of "inode": the data usually contained in the inode (size,
access rights, location of the data blocks, ...) is contained directly
in the directory entry. IOW typical "unix" filesystems have an
additional indirection, where a directory entry only contains a name and
a pointer to an inode (which describes the file), whereas in FAT you
don't have that indirection, which makes it impossible for the file to
exist at several places at the same time (hardlinks) or for a file to
exist without being stored in a directory somewhere.
But maybe there's also something about the tradition from which the OS
grew. In Unix the tradition is to say that it's the applications's
responsability to synchronize between themselves (e.g. locking or
somesuch) when accessing the same file (i.e. the OS doesn't make any
effort to try and prevent them from stomping on each other), whereas
I get the impression that Windows was designed with a more
"restrictive/secure" mindset in this respect.
Stefan