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Forked from Hais/
Last active September 10, 2022 14:37
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Create and manage a case-sensitive disk-image on macOS (OS X).
# ---------------------------------------------------------
# Customizable Settings
# ---------------------------------------------------------
# ---------------------------------------------------------
# Functionality
# ---------------------------------------------------------
create() {
hdiutil create -type SPARSE -fs 'Case-sensitive Journaled HFS+' -size ${VOLUME_SIZE} -volname ${VOLUME_NAME} ${VOLUME_PATH}
automount() {
cat << EOF > "/tmp/com.${VOLUME_NAME}.plist"
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "">
<plist version="1.0">
sudo cp "/tmp/com.${VOLUME_NAME}.plist" "/Library/LaunchDaemons/com.${VOLUME_NAME}.plist"
rm "/tmp/com.${VOLUME_NAME}.plist"
noautomount() {
sudo rm -f "/Library/LaunchDaemons/com.${VOLUME_NAME}.plist"
detach() {
m=$(hdiutil info | grep "${MOUNT_POINT}" | cut -f1)
if [ ! -z "$m" ]; then
sudo hdiutil detach $m
attach() {
sudo hdiutil attach -notremovable -nobrowse -mountpoint ${MOUNT_POINT} ${VOLUME_PATH}
resize() {
hdiutil resize -size ${VOLUME_SIZE} ${VOLUME_PATH}
compact() {
hdiutil compact ${VOLUME_PATH} -batteryallowed
help() {
cat <<EOF
usage: casesafe <command>
Possible commands:
create Initialize case-sensitive volume (only needed first time)
automount Configure macOS to mount the volume automatically on restart
noautomount Stop macOS from mounting the volume automatically on restart
mount Attach the case-sensitive volume
unmount Detach the case-sensitive volume
resize Resize the case-sensitive volume
compact Remove any uneeded reserved space in the volume
config Show current configuration and instructions on changing
help Display this message
config() {
cat <<EOF
The behavior of the script may be modified by setting the following environment variables.
If not set the script will use sane defaults.
Location where case-sensitive volume will be mounted
Current effective value: ${MOUNT_POINT}
Location where image file should be stored
Current effective value: ${VOLUME_PATH}
Name of case-sensitive workspace as visible in macOS Finder app
Current effective value: ${VOLUME_NAME}
Maximum size of volume (will auto-grow up to this)
Current effective value: ${VOLUME_SIZE}
invalid() {
printf "casesafe: '$1' is not a valid command.\n\n";
case "$1" in
create) create;;
automount) automount;;
noautomount) noautomount;;
mount) attach;;
unmount) detach;;
resize) resize;;
compact) compact;;
config) config;;
help) help;;
'') help;;
*) invalid $1;;
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crdesai commented Nov 15, 2017

Thanks for the script. It helped me resolve an issue I was facing with my package. I enabled automount while creating the volume at this time. However, I do not need the volume anymore. How can I make sure OS does not automount it when i restart my machine?

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scottsb commented Nov 16, 2017

@joshka, this wasn't really intended to support multiple mounts, but I don't see any harm in that suggestion, so I'll update it.

@crdesai, I just updated this to include a "noautomount" subcommand as well.

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SPARSEBUNDLE might be a better choice than SPARSE. The bundle appears to split the image into chunks, and therefore works better with backup software which only needs to update the changed chunks after the first copy.

See also:

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tpinne commented Sep 27, 2018

I'm experiencing very very veeeeery bad IO performance since I updated to macOS Mojave. Anyone experiencing the same problem?

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djedi commented Oct 31, 2018

I'm having a number of issues since installing Mojave. I can't seem to mount at all right now. The process just hangs.

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rajpra8 commented Feb 16, 2019

I had similar issue. Look at the original thread that has link to this. Solution was to move to APFS

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amaharana commented Apr 7, 2020

Is there a way to resize the disk image created using this script? I have run out of space on the case sensitive image and changing the value of CASE_SAFE_VOLUME_SIZE while mounting doesn't help. Is my only option to create another image of larger size and transfer the contents? Or is there an easier, more obvious way that I am missing?

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scottsb commented Apr 7, 2020

@amaharana, I just added a resize command that you should be able to use (along with setting CASE_SAFE_VOLUME_SIZE). Note that I have not tested this, as I am not currently using this script myself and don't have one to test with.

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Has anyone used this on Big Sur? I have noticed that if the computer goes to sleep with the image filesystem mounted, interacting with the file system inside the image becomes incredibly slow.... but not consistently so I haven't be able to recreate it well enough to report the bug

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For anyone who comes here, I was having the IO issues @tpinne mentioned but as my previous comment indicated I have only been having them since using Big Sur. I have changed the script so that the filesystem is "Case-sensitive APFS" and so far it seems a lot better... I was barely able to run npm install in directories in the mounted workspace before, now it seems to be working as expected

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Any ideas on how to encrypt this?

I tried to add hdiutil create -encryption flag and enter a password etc, it works properly when I manually mount it but then when I run

hdiutil isencrypted /dev/disk3s1
encrypted: NO

It says not encrypted 🤔 not sure if i'm not thinkin something through properly though

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scottsb commented Aug 8, 2021

Unfortunately, I am no longer using this myself, so I can't advise much. I did do a quick search and found this:

That answer specifically mentions Maverisks so is rather old, but if I'm reading it correctly, it sounds like it's possible for macOS to cache an old encryption status of "no" if a drive with the same path/name is remounted as one that was previously encrypted.

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