How can I get a list of files that changed after any action?

Hi
When I select an action I get a message saying x number of tags have been changed.
How can I get a list of which files they are?

Thanks

Only manually.
You have the following options to check:
Does the number of treated files match the number of selected files (see status bar for that).
If you apply an action, you should know what you have done. Then it should be possible to filter for the result of that action.

I selected all my files 19217 and applied the action to remove trailing spaces \s+$
It says:

Formatted tags in 1816 of 19217 files.
0 of 19217 files renamed.

So how can I see the 1816 files have changed?

Thank You

As I said: only manually. There is no way to filter for just treated files. You would have to do that before.
If you are not sure that an action does what you want, then filter for the files that are likely to be treated before and after the treatment.
Otherwise you have to trust MP3tag.

You can use the datetime stamp of a file as an indicator for the last change.

See Mp3tag/Tools/Options/Tags ...
Set Option "Preserve file modification time when saving tags" to "no".
Close the dialog with "OK".

Then set up a new column in Mp3tag listview ...
Name: File Mod DT
Value: %_file_mod_datetime%
Field:
Sort by: %_file_mod_datetime_raw%
Close the dialog with "OK".

Sort all files by this column and you will get the last modified files at top or at bottom of the file list.

You may apply the Mp3tag Filter using the technical variable ...
%_file_mod_date%
%_file_mod_datetime%
%_file_mod_datetime_raw%
... to display only such files which match the filter criterion.

If you use an action group to apply changes to the files, then you can set a user defined tag field to a value of your wish, afterwards apply the Mp3tag Filter and filter the files for the existence of this tag-field.

DD.20141219.1253.CET

I do not know what the OP wants to find out.
But using a user-defined field as criterion would only prove that the action to fill that usere-defined field was successful. THis would also lead to the effect that the modifaction date would always be updated.
So if you want to be sure that an action really had the effect you wanted, then the modification date is only valid if you execute an action group with a single action in it.

I meant the second proposal, using a self defined tag-field, for people who do not want to change the original date time stamp.

DD.20141219.1343.CET

The easiest way I found was to simply sort by date modified.
I now have another strange problem.
The reason I wanted to see was that I couldn't believe 1816 of my files 19217 had trailing spaces as I'm usually very careful with my tagging.
I undid the action to see if those files really all did have trailing spaces but the first 30 I checked did not so why is mp3tag telling me they did?

Thanks

On what tag-field(s) did you apply the regex-replace-action?
If you did take _ALL did you really look for all tag-fields? Maybe there are tagfieds for which you have not defined a column. And _ALL includes the filename too.

The regex character class \s has several characters.
Test:
$regexp($char(9)$char(10)$char(11)$char(12)$char(13)$char(32)$char(160),'\s',)

DD.20141219.1654.CET

Hello,

you could set the "read-only attribute" of all of your mp3-files. MP3-tag will ask you at any operation if the "read-only attribute" shall be reset. If you reply yes all treated files will have that attribute reset.
With the command "dir /s /a:-r /b" you will get a list of all files which had been changed (and hence have reset read-only attribute