Subject: Re: atime mtime ctime
To: None <firstname.lastname@example.org>
From: Takahiro Kambe <email@example.com>
Date: 11/22/2000 23:06:18
In message <20001122125700.1D7D535DC5@smb.research.att.com>
on Wed, 22 Nov 2000 07:56:58 -0500,
"Steven M. Bellovin" <firstname.lastname@example.org> wrote:
> >One simple way is the time when something created by open(), creat(),
> >mkdir(), mknod(), socket() and so on. But I don't think
> >it is very useful.
> And what about link()? That, I think, is the killer -- the times are
It's not. Although link() create another path name for a file, it
dosen't create inode nor contents for the file. SInce symlink()
creates inode and contents for pointing another pathname, it is
creation of file.
> in the i-node, but "created" is a concept that applies more to
> directory names.
UNIX's file don't have its name by itself, but directory hierarchy
gives the name. So, link() is creating name not a file.
And Still I neve agree with adding support of creating time from now.
> That said, if memory serves correctly ctime *was* originally "created"
> time for a brief period between 6th Edition and 7th Edition. At least,
> I recall seeing some references to that, way back when. ctime first
> appeared in 7th Edition.
Hmmm. Since I've live from 4.2BSD, it's much impressive.
> It's also worth remembering that in those days, there was a lot of
> pressure to keep the inode small. Adding a 4th time field would have
> taken away two disk block entries, which in turn would have lowered the
> threshhold for when "indirect" blocks were needed, thus slowing access
> to the file. Features aren't free, and constrained resources often
> produce far more elegant solutions than today's "memory and CPU are
> free; why not add it?" attitudes.
I perfectly agree.
Takahiro Kambe <email@example.com>