Paths

File and directory paths follow certain conventions. These include the possible use of a drive letter followed by a colon (:), the use of backslash (\) as the path separator, and the distinction between relative and absolute paths.

Forward slash (/) often works when used instead of (\) but not always; it is normally used to mark switches (options). Using forward slash can lead to various obscure behaviors, and is best avoided.

Special device names include NUL, CON, PRN, AUX, COM1, ..., COM9, LPT1, ..., LPT9; these can be redirected to.

Examples:

• attrib C:\Windows\System32\notepad.exe
  • Succeeds if the file exists, as it should. This is an absolute path with a drive letter. It is also known as a  fully qualified path.
• attrib \Windows\System32\notepad.exe
  • Succeeds if the current drive is C:, and if the file exists, as it should. This is an absolute path without a drive letter.
• cd /d C:\Windows & attrib System32\notepad.exe
  • Succeeds if the file exists. The path given to attrib is a  relative path.
• cd /d C:\Windows\System32 & attrib C:notepad.exe
  • Succeeds if the file exists. The path given to attrib is a  one despite containing a drive letter: there would have to be C:\notepad.exe with a backslash for that to be an absolute path.

    relative

• cd /d C:\Windows & attrib .\System32\notepad.exe
  • Succeeds if the file exists. A single period denotes the current folder.
• attrib .
  • A single period denotes the current folder.
• cd /d C:\Windows & attrib .\System32\\\notepad.exe
  • Succeeds if the file exists. Piling of backslashes has no impact beyond the first backslash.
• cd /d C:\Windows & attrib .\System32
  • Succeeds if the folder exists.
• cd /d C:\Windows & attrib .\System32\
  • Fails. Folders are usually denoted without the final backslash.
• cd C:\Windows\System32\
  • Succeeds.
• cd ..
  • A double period denotes the parent folder.
• attrib C:\Windows\System32\..\..\Windows\System32
  • A double period can be used in the middle of the path to navigate to the parent folder, even multiple times.
• attrib \\myserver\myvolume
  • A network UNC path starts with double backslash and no drive letter.
• cd \\myserver\myvolume
  • Does not work; changing to a server folder in this direct manner does not work.
• pushd \\myserver\folder
  • Automatically creates a drive for the folder and changes to it. After you use POPD, the drive gets unassigned again.
• attrib C:/Windows/System32/notepad.exe
  • Succeeds on multiple versions of cmd.exe. Uses forward slashes.

Links:

• Long filenames, NTFS and legal filename characters at ss64.com
• Naming Files, Paths, and Namespaces at Microsoft
• W:Path (computing)#MS-DOS/Microsoft Windows style, wikipedia.org
• Why does the cmd.exe shell on Windows fail with paths using a forward-slash ('/) path separator