#!/bin/sh

DISKSIZE_MB=16
DISK=disk.img
OFFSET=1048576

dd if=/dev/zero of="$DISK" bs=1M count="$DISKSIZE_MB"

sfdisk "$DISK" <<EOF
label: dos
label-id: 0x7c295044
device: disk.img
unit: sectors
sector-size: 512

disk.img1 : start=        2048, size=       30720, type=4
EOF

LOOPDEV="$(losetup -f)"
losetup "$LOOPDEV" "$DISK" -o "$OFFSET"
mkfs.fat -F16 "$LOOPDEV"
losetup -D "$DISK"