[TUHS] When/how did ctime change from inode "creation" to "change" time?

[Larry McVoy]

I had the exact same reaction, I think I saw the time created and liked 
that semantic.  When it morphed into inode change time, as a source
management guy, I'd much rather have create time than changed time
since I already got access and modified times.

On Wed, Mar 12, 2025 at 01:31:37PM +1100, Rob Pike wrote:
> Or perhaps the comment was wrong?
> 
> I do remember being confused by it.
> 
> -rob
> 
> 
> On Wed, Mar 12, 2025 at 1:19???PM Theodore Ts'o <tytso at mit.edu> wrote:
> 
> > As part of a discusion on the Linux kernel mailing list, there was an
> > assertion that ctime was orginally "creation time".
> >
> > From the v7 sources in TUHS, we can see:
> >
> > struct dinode
> > {
> >         unsigned short  di_mode;        /* mode and type of file */
> >         short   di_nlink;       /* number of links to file */
> >         short   di_uid;         /* owner's user id */
> >         short   di_gid;         /* owner's group id */
> >         off_t   di_size;        /* number of bytes in file */
> >         char    di_addr[40];    /* disk block addresses */
> >         time_t  di_atime;       /* time last accessed */
> >         time_t  di_mtime;       /* time last modified */
> >         time_t  di_ctime;       /* time created */
> > };
> >
> > ... although the v7 kernel sources does seem to update ctime when the
> > inode metadata changes, regardless of what the coment in
> > /usr/src/sys/h/ino.h might say.
> >
> > More interestingly, this comment seems to continue in newer versions
> > up to 3BSD, and then the comments becomes "change time" in BSD 4.2,
> > probably coincident with the File System Implementation?
> >
> > The best we can guess is that the change from "creation time" to
> > "inode change time" happened sometime between 1979 and 1982.  Does
> > anyone who was around can give the story about how and when this
> > happened?
> >
> >                                         - Ted
> >

-- 
---
Larry McVoy           Retired to fishing          http://www.mcvoy.com/lm/boat