15.3.5.4 Windows File Name Case

Windows normally folds case when referring to files, unlike Unix. That is, on Windows, the file names `file', `File', and `FiLe' all refer to the same file. You must be aware of this when porting Unix programs to Windows, as the Unix programs may expect that using different case is reflected in the file system.

For example, the procedure used to build the program perl from source relies on distinguishing between the files PERL and perl. This fails on Windows.

As a matter of interest, the Windows file system stores files under the name with which they were created. The DOS shell displays the names in all upper case. The Explorer shell displays them with each word in the file name capitalized.