⎕NTYPE Get/Set the file type/creator for a MacOS file

This function is used in MacOS to set the type and optionally the creator of a native file. The file type is a 4-character code which defines, under MacOS, the class of file. For example, 'TEXT' is the type for ordinary text files, and 'APPL' is the type for a program file. The creator of a file is also a 4-character code, and is used by the operating system to associate a file with an application. For example, when you double-click on a document file, the creator determines which application is started up in order to open the document.

The syntax of ⎕NTYPE is:

          ⎕NTYPE FILENAME
          TYPE ⎕NTYPE FILENAME 
or        TYPE ⎕NTYPE TIENO

The right argument is either a character vector specifying the name of the file (including the path), or an integer tie number if the file has already been tied using ⎕NTIE. Omitting the left argument simply returns the current type and creator.

If you want to set just the file type, and not the creator, you supply a character vector of 4 characters as the left argument. If you want to set both the type and the creator, you can supply a 2-element nested vector; the first element is the type, and the second the creator. Both are 4-element character vectors.

Under operating systems other than MacOS, this system function exists in APLX, but it has no effect.