Nautilus-Columns

Question

I have installed nautilus-columns as I wished to view and sort files by the date they were created rather than last modified, but I find that whilst it works for mp3 files it doesn't seem to for ogg. Similarly it works for jpeg but not tiff or raw image files.

Is this behaviour to be expected or has something gone wrong with installation?

Any help would be most welcome.

Thanks,

Steve

score 1 · Accepted Answer · answered Feb 01 '15 at 19:16

In unix, there is no such a thing as the creation time.

There is a semantic problem here: If I have a file a.txt first created on oct, 1st , and I create a new file by cp a.txt b.txt on nov, 1st, what is the creation time of b.txt? If you think about nov, 1st. think that I can

ln a.txt b.txt 
rm a.txt

and have the same final effect: b.txt contains exactly the data of a.txt, but the metadata linking to the content is created on nov, 1st...

It will heavily depend on the filesystem where you have your files stored. Unix-type file system (like all the default linux file system --- ext4, etc.) have no metadata for the first creation date. If you see the manual page for fstat(2), you can see that the data for files is:

          time_t    st_atime;   /* time of last access */
          time_t    st_mtime;   /* time of last modification */
          time_t    st_ctime;   /* time of last status change */

There is an old ongoing confusion on that ctime means creation time (as it is on some MS-DOS derived file system) but in unix there is no such a thing as the first time of creation of a file.

So no, in normal unix filesystem you do not have the creation time. You just have the last metadata modification time.

Thank you very much for your reply, it is very interesting and very much appreciated! Regrettably I am a beginner and some of the finer points are lost on me but I understand the general idea. As someone who works professionally with audio and video it's particularly interesting as the creation date can be critical with photographs and audio and videos files. I that case the original point at which a photograph is taken still remains relevant even if it is cloned and edited. Or am I missing something? Thank you again for taking the time to reply! — Steve Brodie, Feb 02 '15 at 20:51
@SteveBrodie The data you are referring to is better stored (as it is - search EXIF for jpg files, for example) into the file data itself, where they are safer, and better defined. Think about your camera: you shot a photo yesterday, and the file is copied to your PC today. The second file is created today... — Rmano, Feb 02 '15 at 21:26
Yes that is helpful reply thank you and I do see the point. Re my OP it is the EXIF data which the nautilus-columns extension displays, so I guess it would do the job I need if I could get it to work!:) — Steve Brodie, Feb 04 '15 at 08:41

score 1 · Answer 2 · answered Feb 26 '15 at 14:37

As a sort of post script, I have realised that 'Image Viewer' (bundled with Ubuntu 14.04) is a very good place to view EXIF data.

In Image Viewer just select 'View>Side Pane' or 'Ctrl F9'. Even more info is available by selecting 'Details' at the bottom of the sidebar.

This helped me with the initial problem of wanting to view the date a photo was taken, if not the issues experienced trying to run nautilus-columns.

Thought I'd post this as I was unaware that Image Viewer had that capability, I hope it may help someone else!

Nautilus-Columns

2 Answers2