Editing FourCC (section)

=== In Apple systems ===
Since [[Mac OS X Panther]], OSType signatures are one of several sources that may be examined to determine a [[Uniform Type Identifier]] and are no longer used as the primary data type signature. Mac OS X (macOS) prefers the more colloquial convention of labelling file types using file name extensions. At the time of the change, the change was a source of great contention among older users, who believed that Apple was reverting to a more primitive way that misplaces [[Metadata (computing)|metadata]] in the filename.

Filesystem-associated type codes are not readily accessible for users to manipulate, although they can be viewed and changed with certain software, most notably the macOS command line tools ''GetFileInfo'' and ''SetFile'' which are installed as part of the developer tools into ''/Developer/Tools'', or the [[ResEdit]] utility available for older Macs.<ref>{{citation | url = https://developer.apple.com/documentation/Darwin/Reference/ManPages/man1/GetFileInfo.1.html | title = Darwin reference | contribution = GetFileInfo | type = man page | publisher = Apple}}</ref><ref>{{citation | url = https://developer.apple.com/documentation/Darwin/Reference/ManPages/man1/SetFile.1.html | title = Darwin reference | contribution = SetFile | type = man page | publisher = Apple}}</ref>