FTP: Can I overwrite a file and maintain it's modified date?

Question

I have hundreds of mp3 files on my server. Each file's modified-date is important because it is fetched by PHPs filemtime to represent it's upload date (since there's no way to determine an upload time without storing values in a database).

I have come across an audio issue in which all the files need to be normalized and re-uploaded to the server. This would, of course, change the modified-date of each file to "today". I need each file to retain it's original modified-date.

I'm not sure if this is a software-recommendation question or a programming question, so I apologize if this is the wrong .SE site. Is this even possible?

Answer 1

I know this isn't the answer you're looking for, but it would make far more sense to start storing this information in a database than relying on the last-modified date. This way you can show your users the date that they need to know and retain the true date of modification.

An approach like this also gives you much more flexibility.

As requested by @Snailer - for the sake of closing the question.

Answer 2

You should be able to set the modified time with touch: http://php.net/manual/en/function.touch.php

This requires PHP > 5.3 and the user running the script (probably your web user unless you run it from the cli) needs to have write permission on the file.

You have two options for implementation:

1. Store the filenames and their mtimes in temporary storage (either a file or a database table). When you finish the upload, run through all of the files and use touch to reset the mtime.

2. As you upload the files, check to see if the file already exists. If it does, grab the mtime in a temporary variable, overwrite the file, then touch it with the correct mtime.