The formats might be anything, but are mostly HTML. More specifically, they're mostly downloaded news articles. The publication date is the date you see at the top of most articles, along with the author.

Other file formats are mostly PDF, and in this case the publication date is determined by what's in the PDF. It might be a book with only a year for the date, a report where the publication date might be anywhere or not even included, a government document, etc. All have different text formats and locations for the date, so automating the search for it is out of the question.

I tried writing a software program to do this with HTML files in Visual Studio for Windows. I learned that it's not easy to automate the process of looking for the right date and being sure you get the right one, even just with HTML, so the files have to be viewed manually. That I can accept. But having to use the touch command in bash to edit the file's date requires too much work when dealing with a lot of files, since I would have to look at each HTML file in a browser, then cut/paste the file name and add the proper date in bash for the touch command. Many HTML files have encrypted text, including the date of publication of the article, so that's another problem that has to be considered if you think you can automate this with a script.

A simple date changing utility that works in Gnome's file manager is all I really need. Anyone in this forum for software who suggests using some bash script is off-topic, in my opinion. It won't work anyway. I only mentioned the touch command because that's the only way I currently know how to do it, but it's not really something for bash to handle. It's not even easy to automate with a programming language.

Like I said in my OP, I'll need to open each file in a directory to see the publication dates before changing their modification dates.

The gnome's default file manager has not an option nor an extension to change the file's timestamps. But it has the capability to integrate scripts.

So you either install a file manager that can do that (we suggested filecommander and doublecommander) or make a script for the file manager "files" to cover this feature (help here).

I can't see any other option for you.

Not off topic at all. A right click menu that runs a bash script fits your simple date changing utility requirements. I've expanded it a bit to include a simple date verification and uses current time.

Easy is relative - none of the problems you've raised are insurmountable.

Still, if we pretend they are, there's remains a straight-forward solution:

1. Export the file names and modified dates to a tab-separated text file, and open it in suitable software (e.g. LibreOffice Calc)
2. Manually view relevant files and add copy-paste publish dates in a third column, then afterwards ensure each one is accepted as a date and reformatted to a suitable format.
3. Save the result as tab separated file, then write a Bash script to while/read loop through and touch the files.

This can be done any number of ways, easily. Loop through the files that you want to change. Doesn't matter what type of file it is.

Another example:
File loop:

Do you think that's a straightforward solution? That would require at least as much work as using touch in bash.

I'm trying to minimize the steps needed to perform the task. I posted in the software forum because I thought there might be a software package out there that someone knows about.

Having actual experience in trying to solve a problem is more enlightening than imagining that you can solve it.

I have little knowledge of what that's doing and there aren't any comments to explain it, but it looks like overkill on the data it produces and doesn't seem to take into account the fact that I need to look inside each file to get the proper publication date before I can change it.