Reading and writing HFS floppies

Transferring files from classic to modern Mac OS

This is a slightly-janky way to copy files to and from HFS-formatted floppies created on System 6 or 7. It works on modern macOS with a USB floppy drive and 1.44 MB disks. 400K and 800K disks don’t work in modern drives.

Setup

Install hfsutils via Homebrew.

brew install hfsutils

You need root access to do anything else beyond this point, so run sudo -s to get a root shell.

The utilities try to be smart about where the files are located, so prefix all disk paths with : to ensure it looks at the floppy drive instead of the local filesystem.

Usage

Use diskutil list to find the floppy drive’s device name /dev/diskN.

$ diskutil list
[...]
/dev/disk14 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                                                   *1.5 MB     disk14

Mount the disk and do copy operations.

hmount /dev/diskN # mount the floppy drive

hls # get a list of files

hcopy :diskfile ~/localfile # copy FROM floppy
hcopy ~/localfile :diskfile # copy TO floppy

humount # unmount the floppy drive

Copying to disk will result in files that do not have the correct creator and type codes, so they won’t be recognized by the classic Mac. Use hattrib to set the correct attributes.

hattrib -c 'ttxt' -t 'TEXT' :diskfile # SimpleText

Setup

Usage

All commands