On 2017-12-13 22:13:44 +0000, Tim Streater said:
In article , nospam
wrote:
In article , J. P. Gilliver (John)
wrote:

This whole issue is just another bit of fallout from the Windows
nonsense of *requiring* a file extension.

What nonsense might that be? Windows (and DOS) don't require an
extension; OK, they normally _use_ one (and I definitely agree with all
who think hiding them's a bad idea and certainly shouldn't be the
_default_), but there's no _requirement_.

Of course it is a requirement. Quick, go change a .exe to have no
extension and see what happens when you try to run it, Or change any
file with an extension and then try to use it as intended.

I'm not sure how to run a .exe without an extension, but that doesn't
stop me having the file. Certainly, I can have say a Word file without
.doc and open it in Word, or a text file without .txt and open it in
Notepad. If by "as intended" you mean "by double-clicking on it",
that's what extensions are _for_; but they're certainly not a
_requirement_.

Your comment that they are required would only make sense if, in some
other OS you are familiar with, you can have filenames without
extensions that still open in the appropriate application by being
double-clicked on (or equivalent operation in that OS).

classic mac os did exactly that.

Yes and no.

Classic Mac OS doesn't need filename extensions as such, but does have
a similar technique stored within the file's Finder data (the File Type
and Creator codes). These just aren't visible to the general user
without using something like ResEdit, Resourcer, FileBuddy, etc.



And that is still the case, AFAICT. I just removed .tiff from a file
and double-clicked it. Still opened in Preview.

That's because *that* file had already been set as a TIFF and
associated with Preview. The preference has already been stored in the
Finder's data files and the OS doesn't bother to change that ... unless
you change the filename extension to a different one (try changing the
filename extension from .tiff to .docx, for example, and see what
happens when you double-click it).

Try saving a TIFF file without the extension and then double-clicking
it. Finder will ask you what to open it with, and then associate that
choice with that file.





The type of a file and which app you'd like it to open with are items
of file metadata and have no business being part of the filename.

It is useful and sensible to have the file type as part of the
filename. Otherwise you'd get a pile of files which neither you nor the
OS having any idea whether they are images, sounds, text, etc. You
would then have to try to open the file in every app you own until you
found one that could open it ... you can't rely on the OS to do that
since a JPEG image file can actually be opened in a text editor as the
file's data, even if it's rarely useful to do so.