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This question already has an answer here:

Before you start complaining about me not googling the answer - I did Google search it.

But everything I could find was that CON, COM1, AUX, etc are restricted because they have special meaning - for example, "CON:" mens console. And therefore writing to CON: will result in the text popping up in the console (checked that myself - typing echo "asdf" > CON: indeed resulted in "asdf" showing up).

For me, this still hardly answers the question. I mean, CON: should be something different that "C:\CON" or "C:\CON.txt", shouldn't it? As far as I know, any file or folder or driver on anything is being fully identified by the string containing it's full location (including the drive followed by a : sign at the beginning) and (optionally) it's type extenstion. Therefore I can't see how, for example, the existance of a file "C:\Documents and Settings\Someone\Desktop\c.docx" could result in any ambiguity, as it should be obvious that this Word document is not the C: drive. And similary I can't see how the existance of "C:\Documents and Settings\Someone\Desktop\con.docx" could result in Windows not knowing whether this is a Word document or the console.

Could someone explain this to me? Thanks in advance.

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marked as duplicate by Ƭᴇcʜιᴇ007, Tog, Heptite, random Jan 12 '14 at 23:30

This question was marked as an exact duplicate of an existing question.

This one is probably my favorite answer due to explanation and additional information sources: – Ƭᴇcʜιᴇ007 Jan 11 '14 at 23:42
Everything you read answers the question because "reserved" means what it means. For there to be no conflicts, you do not use it or any weird combination you personally think makes sense. Hilarious things happen when you break the rules. These reserved items are used for among other things printer port naming, even in the latest versions of Windows. – Fiasco Labs Jan 12 '14 at 0:15
@techie007: RATS! I did Google search the topic, and I DID read... /some/ of the answers you listed. And since they didn't make everything clear to me, I posted this question. However... it seems I indeed hadn't read everything carefully enough. You're right, this one: solves my problem. Sorry. – gaazkam Jan 12 '14 at 12:48
No problems, you posted a good question, it just happens to have been asked. Welcome to SU! :) – Ƭᴇcʜιᴇ007 Jan 12 '14 at 18:10

A document can be minimally referred to by its filename only. When this happens, the OS will assume that the file is in the current working directory. In other words, while it's perfectly OK to fully qualify the file path (drive/directory/filename), it's also OK to enter just the filename. DOS didn't support subdirectories until DOS 2.0, but all version of DOS had CON.

CON was often used for file input. Typing COPY CON filename in DOS and Windows allows the user to type a series of text - hitting CTRL/Z or F6 would then copy the text into the file with the name filename.

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OK, so this answers the "full path" part, thanks. But what about the extensions? How could "con" be mistaken with "con.txt" or "con.mp3"? Even disregarding their full path, they have entirely different names! – gaazkam Jan 11 '14 at 23:20
Not to the operating system... – Fiasco Labs Jan 12 '14 at 0:17
@gaazkam: It's explained in more detail by The Old New Thing. – grawity Jan 12 '14 at 1:01
@grawity: And that answers my question - thank You very much, Sir! – gaazkam Jan 12 '14 at 12:44

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