Maximale Pfadlaenge bei Windows 7

Short vs. Long Names

A long file name is considered to be any file name that exceeds the short MS-DOS (also called 8.3) style naming convention. Typically, Windows stores long file names on disk as special directory entries, which can be disabled systemwide for performance reasons depending on the particular file system. When you create a long file name, Windows may also create a short 8.3 form of the name, called the 8.3 alias, and store it on disk also. This 8.3 aliasing can be disabled for a specified volume.

    Windows Server 2008, Windows Vista, Windows Server 2003, and Windows XP:  8.3 aliasing cannot be disabled for specified volumes until Windows 7 and Windows Server 2008 R2.

On many file systems, a file name will contain a tilde (~) within each component of the name that is too long to comply with 8.3 naming rules.

Note  Not all file systems follow the tilde substitution convention, and systems can be configured to disable 8.3 alias generation even if they normally support it. Therefore, do not make the assumption that the 8.3 alias already exists on-disk.

To request 8.3 file names, long file names, or the full path of a file from the system, consider the following options:

    To get the 8.3 form of a long file name, use the GetShortPathName function.
    To get the long file name version of a short name, use the GetLongPathName function.
    To get the full path to a file, use the GetFullPathName function.

On newer file systems, such as NTFS, exFAT, UDFS, and FAT32, Windows stores the long file names on disk in Unicode, which means that the original long file name is always preserved. This is true even if a long file name contains extended characters, regardless of the code page that is active during a disk read or write operation.

Files using long file names can be copied between NTFS file system partitions and Windows FAT file system partitions without losing any file name information. This may not be true for the older MS-DOS FAT and some types of CDFS (CD-ROM) file systems, depending on the actual file name. In this case, the short file name is substituted if possible.