POSIX Compliance

POSIX compliance permits UNIX programs to be ported to Windows NT. Windows NT is fully compliant with the Institute of Electrical and Electronic Engineers (IEEE) standard 1003.1, which is a standard for file naming and identification.

The following POSIX-compliant features are included in the NTFS file system:

• Case-sensitive naming. Under POSIX, README.TXT, Readme.txt, and readme.txt are all different files.

• Hard links. A file can be given more than one name. This allows two different filenames, which can be located in different folders, to point to the same data.

• Additional time stamps. These show when the file was last accessed or modified.

Caution You must use POSIX-based programs to manage filenames that differ only in case.

Using POSIX-based programs, you can create case-sensitive filenames, where two or more filenames can differ only in case (for example, annm.doc and AnnM.Doc).

While the Windows NT file systems support both case-preservation and case-sensitivity, you cannot use standard commands to manage filenames that differ only in case. (Standard commands include those used at the command-line — such as copy, del, and move — and their My Computer and Windows NT Explorer equivalents.) For example, if you type the following at the command prompt:

del AnnM.Doc

both annm.doc and AnnM.Doc are deleted.

For more information about POSIX, see Chapter 29, "POSIX Compatibility."