File times in 4.[23]

[Chris Torek]

In article <7053 at boring.mcvax.UUCP> jack at mcvax.uucp (Jack Jansen) writes:
>... we noticed that the behaviour of file access times under 4.3
>is not according to the manual. ...
>Manual: access time changed by read, write and some others.
>	modify time changed by write
>	creation time changed by link, chmod, etc.

Hold!  /There is no creation time!/  `ctime' is `last change' time.
It should be updated any time the disk inode is changed in any way,
so that the file is properly backed-up.

>4.2:	access time changed by read *only*.
>	modify time changed by write
>	creation time changed by link, *but not chmod*.

If chmod does not update inode ctimes, it is rather seriously broken.
A full restore of a file system could leave many files with the wrong
modes.

>4.3:	access time changed by read *only*.
>	modify time changed by write
>	creation time never changed (except by creation, of course).

This last is most certainly untrue.

>Especially the fact that the access time doesn't change on write
>looks like a bug to me....	

No: here the manual must be in error.  `access' means `read', more
or less.

The `ls' manual is buggy; it claims that `ls -c' sorts on, and/or
prints, file creation times, when in fact no such times are available.
Are there others that make similar claims?
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 1516)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris at umcp-cs		ARPA:	chris at mimsy.umd.edu