How to Create a Virtual Floppy Under OSX

The objective is creating a mountpoint on the system as it were a normal floppy disk, formated with MS-DOS FAT, I use this virtual disks to test my operating system kernel under Bochs.

To start with I create 1.44 Mb file, with .dmg extension

dd if=/dev/zero of=./disk.dmg bs=10 count=147456

After that I attach it to the /dev tree, I do it without assigning a mountpoint, as the disk is not yet formated and would give us an error

hdid disk.dmg -nomount

This will return something like : /dev/disk1 . Now the disk needs to be formated and given a label

diskutil eraseDisk MS-DOS Label disk1

We can now normally mount the /dev/disk1 to the mountpoint we want.

One Response to “How to Create a Virtual Floppy Under OSX”

  1. alex says:

    Hi,
    I know it’s a pretty old post, anyway
    I tried following the guide above but the command: “diskutil eraseDisk MS-DOS Label disk1″ returns an error:

    error creating partition map: (-5344)

    Partitioning encountered error on disk disk3: MediaKit reports not enough space on device for requested operation (-5344)

    seems It cant fit in the 1.44MB image…

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