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I guess the title just about says it all. And yes, .\, not that obsolete \. thing.

For those who don't know, .\ is a shorthand way of saying "this computer"*see "footnote" in Windows at a logon screen, which comes in very handy when you don't know or care about the local computer name but need to authenticate against it anyway, such as through RDP or scripting against a set of shared local users and passwords or even locally, if you're unlucky enough to have to physically go to a machine.

Does this have an actual name, and if so, what is it? I feel kind of stupid saying the dot-slash thing, which is how I've been referring to this.

*Footnote: As pointed out by @OliverSalzburg , the . is actually the shorthand for "this machine" and the \ serves as a separator between hostname and username when using the [host]\[user] style of authentication against a Windows machine.

masegaloeh
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HopelessN00b
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    +1 I didn't know that ".\" was shorthand for "\", thanks for the TIP! – HeatfanJohn Sep 21 '12 at 13:27
  • never really thought about it, but maybe it's similar to Linux .\ for "current directory"? Or perhaps that was a simple enough "variable" character for MS to use? – TheCleaner Sep 21 '12 at 13:28
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    I've always referred to it as "Local", I guess from the way that `.` and `(Local)` can be used interchangeably in SQL Server Management Studio. Incidentally, you don't even need the dot in most cases - certainly when I've connected to UNC paths on remote machines and wanted to use an account on that machine, I've just used `\Username` – Chris McKeown Sep 21 '12 at 13:36
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    `.\ ` is not the shorthand. `.` is. The backslash is always used to delimit host from user. – Oliver Salzburg Sep 21 '12 at 14:04
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    @Oliver Salzburg While that is technically true, I don't imagine that a question asking what the name of the `.` character is would have been a constructive or useful way to spend anyone's time. – HopelessN00b Sep 21 '12 at 15:22
  • It should perhaps be noted that this doesn't work on Windows XP. I imagine it was introduced in Vista. – Harry Johnston Sep 24 '12 at 01:10
  • @HarryJohnston My environment at $[megacorp] is mostly XP clients. it works fine on XP. – HopelessN00b Sep 24 '12 at 04:17
  • @HopelessN00b: odd; it doesn't work on *my* XP clients. I just tried it again to make sure, and it definitely isn't working for me. Works fine on all the Windows 7 machines though. Perhaps it's affected by a group policy setting or something. – Harry Johnston Sep 24 '12 at 20:17
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    Just to avoid confusion, it is known as Dot BACKslash NOT dot slash –  Sep 18 '14 at 10:59
  • This is also security concern unfortunately, during penetration testing if server name is displayed when ./ is used in username box it is classified as medium risk. Most of the hardening guidelines suggest disabling this. – J.Pruchnik Apr 22 '15 at 09:03
  • In place of `.`, `` also works. – RBT Jun 13 '17 at 09:41

2 Answers2

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No, there is no specific name for that combination for logging on. Many people have their own name for it but Microsoft never gave it a name and no pseudo standard has ever evolved. The use of ".\" was used because it was already used for file system addressing and it made sense to extend it to machine reference. The nearest it ever came to getting an official name is that "." is called "this" but that is quite unofficial.

John Gardeniers
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The "." simply resolves to the local "whatever" in the PATH/URI systems. So on a file system the "." means the current directory, and in the domain field meands the current system. The "\" delimits domain from user, so .\ literally resolves to the current system with the username to follows. If you're looking for a name for the shorthand - we've always referred to it as "localhost" though that's not strictly accurate (in the URI scheme ./ would be localhost).

iivel
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  • `in the URI scheme ./ would be localhost` <- In a URI "." would be a the end of a DNS entry, so the root zone. Not localhost. – Chris S Sep 18 '14 at 13:49