Macintosh file type and creator data

Updated July 5, 2022 e2106d0 retrocomputing

Sometimes when transferring a file from a modern computer to a classic Macintosh (e.g., System 7), its resource fork disappears into the great aether for certain reasons. As a result, the Mac doesn’t know what type of file it is and can’t open it. Specifically, the OS needs to know the Type and Creator metadata that was stored in the resource fork.

To correct a missing resource fork, use ResEdit. But what are the correct Type and Creator entries? That’s where this table hopefully comes in handy!

File Type Creator
Disk Copy image (img, image) dimg ddsk
StuffIt archive (sit) SIT! SITx
Toast CD image (toast) hImg CDr3