Extension Edit

HeavyMetal · Post by **HeavyMetal** » Tue Aug 16, 2005 8:19 pm

Okay this is probably a dumb question, but I'll ask anyway.

Okay I was wondering what the side effect of changing a file extension is?

Not something like AVI to MPG, but if I delete the vb off of an .rmvb file to make it .rm will this cause problems?

So far it has not. I'm not sure anything really plays .rmvb well, so that is why asked.

Iamshadowkiller · Post by **Iamshadowkiller** » Tue Aug 16, 2005 8:33 pm

there is no side effect good sir, let your heart rest...however, that will not change anything about the file itself..you could probably rename it .shoehorn and load it in to mediaplayer classic and it would still play the same..though this I have not tried

/end

Zarxrax · Post by **Zarxrax** » Tue Aug 16, 2005 9:03 pm

Yes, it will cause problems. There is absolutely NO logical reason to change a file extension to something different that what it is supposed to be. Many media players are smart enough to determine what type of file is by examining the file itself, rather than just looking at the extension, but not all players do this. Don't change your file extensions, ever.

Iamshadowkiller · Post by **Iamshadowkiller** » Tue Aug 16, 2005 9:09 pm

I stand corrected then

/end

trythil · Post by **trythil** » Tue Aug 16, 2005 9:36 pm

Zarxrax wrote:Yes, it will cause problems. There is absolutely NO logical reason to change a file extension to something different that what it is supposed to be.

There's no real reason for file extensions, either...

Scintilla · Post by **Scintilla** » Tue Aug 16, 2005 9:53 pm

trythil wrote:
Zarxrax wrote:Yes, it will cause problems. There is absolutely NO logical reason to change a file extension to something different that what it is supposed to be.
There's no real reason for file extensions, either...

Nonsense, they make it easier to remember just what filetype any given file has.

And, you know, the whole thing about associating extensions with specific programs, which I thought was the whole reason they came up with file extensions in the first place.

Zarxrax · Post by **Zarxrax** » Tue Aug 16, 2005 9:55 pm

trythil wrote:There's no real reason for file extensions, either...

Then I have a question for you. When you are working at the command line in your lunix... how do you know what type of file something is? I think file extensions are primarily for the user... it lets you know immediately what type of file something is. I mean... what if you just have this file called "stuff"? What the hell is it? Is it audio? Video? Text? File extensions serve the purpose of telling you what type of file it is.

[paizuri: Fixed quote.]

Kalium · Post by **Kalium** » Tue Aug 16, 2005 10:43 pm

Zarxrax wrote:Then I have a question for you. When you are working at the command line in your lunix... how do you know what type of file something is? I think file extensions are primarily for the user... it lets you know immediately what type of file something is. I mean... what if you just have this file called "stuff"? What the hell is it? Is it audio? Video? Text? File extensions serve the purpose of telling you what type of file it is.

File extensions are an aniquated system of doing this. Now we use /etc/magic (I kid you not), which uses the first three (I think) characters of a file to determine type and associations.

trythil · Post by **trythil** » Tue Aug 16, 2005 10:56 pm

Kalium wrote: File extensions are an aniquated system of doing this. Now we use /etc/magic (I kid you not), which uses the first three (I think) characters of a file to determine type and associations.

It's more sophisticated than that, but the principle is the same. file(1) uses the magic file, and performs filesystem tests, magic number tests (magic numbers are defined in the magic file) and language analysis (in the case of text files, to differentiate between e.g. ASCII and UTF-8 English text).

Zarxrax wrote:
trythil wrote:
Zarxrax wrote: There's no real reason for file extensions, either...
Then I have a question for you. When you are working at the command line in your lunix... how do you know what type of file something is? I think file extensions are primarily for the user... it lets you know immediately what type of file something is. I mean... what if you just have this file called "stuff"? What the hell is it? Is it audio? Video? Text? File extensions serve the purpose of telling you what type of file it is.

file(1)

For example:

Code: Select all

trythil@nevrast /mnt/usb/video/amv/MultiEditor $ file DDR4
DDR4: RIFF (little-endian) data, AVI, 512 x 384, 29.97 fps, video: DivX 5, audio: MPEG-1 Layer 3 (stereo, 48000 Hz)

It's correct more often than some extension is, because it actually analyzes unique characteristics of files. It's fast, too.

Or, if I'm using a graphical interface, my desktop environment lets me know what the file type is. If I need to see inside it, my desktop environment gives me that capability with a single click. Finally, I can differentiate between various types of text files by their unique name, not by some cryptic extension.

Scintilla wrote: Nonsense, they make it easier to remember just what filetype any given file has.

Modern environments can determine that automatically. A good, long-standing example: Mac OS has been doing that for a decade or so.

Scintilla wrote: And, you know, the whole thing about associating extensions with specific programs, which I thought was the whole reason they came up with file extensions in the first place.

It was a scheme imposed by technical limitations that no longer exist. When you're limited to, say, 6-8 characters, you can't describe a file too well, so you need some extra data to identify it. That is no longer true. Modern filesystems don't even care about the "extension" field anymore.

This isn't to say I don't use file extensions every now and then. It's a nasty habit that's hard to break.

Keeper of Hellfire · Post by **Keeper of Hellfire** » Wed Aug 17, 2005 2:31 am

trythil wrote:
Scintilla wrote: And, you know, the whole thing about associating extensions with specific programs, which I thought was the whole reason they came up with file extensions in the first place.
It was a scheme imposed by technical limitations that no longer exist.

Windows still uses file extensions to associate programms with files. Because Windows runs on over 90% of all PC's, it's for the most people not a good idea to change extensions. There is one exeption of this: If a program denies to open a specific file because of the extension and you know a different extension for the same contents which will work for the progam.