create a DMG file on the command line

Sometimes you might not want to fiddle with the Disk Utility.

Instead, you can do it on the command line.

1. Open Terminal.app

2. Run this:

hdiutil create -encryption -size 2m -fs HFS+ -volname DISKNAME ~john/DISKNAME.dmg

This will create a 2 megabyte sized disk image, in HFS+ format, encrypted. It will ask for a password.

3. You can also convert formats, e.g. ISO to IMG

hdiutil convert -format UDRW -o raspbian.iso raspbian.img

Popular posts from this blog

The most useful defaults-write options

The following are really useful options to set system-wide for Mac OS X. I'd suggest reading them to guess what they do. You should be able to safely run all of them except the first one which tells spotlight (the search function) to ignore any attached drives forever. If you find that drives take a long time to unmount (eject), then usually it is because spotlight is indexing them (reading them in their entirety) to see what they contain. Hence if you find a disk doesn't want to eject, turn off spotlight for that drive. sudo defaults write /.Spotlight-V100/VolumeConfiguration Exclusions -array "/Volumes" defaults write com.apple.dock springboard-columns -int X defaults write com.apple.dock springboard-columns -int 10 defaults write com.apple.dock springboard-rows -int 7 defaults write com.apple.dock springboard-rows -int 5 defaults write com.apple.dock springboard-rows -int 5 springboard-columns -int 10 defaults write com.apple.dock springboard-rows -int X defaults w...
Read more

Erasing firmware password

Image
On some occasions, like myself, you may be forgetful, and forget what you set your bootup ("firmware") password to. Unfortunately for you, if you boot in recovery mode using Command-R, it still wants you to remember your original password to erase the old one.  The proper way to do this is to take the computer to Apple with proof of purchase and they will do it for you. However, if like me you only buy their much older machines due to their upgradability, you may find that you don't have proof that you bought it in an apple store, e.g. second hand, or you lost the proof years ago. So, how do you reset it? The answer unfortunately, is with great difficulty. This blog page tells you how. Please note that I disclaim responsibility for the below - if you blow up your Macbook it's your fault. Do not follow these instructions. I followed these: https://blog.wzhang.me/2017/10/29/removing-mac-firmware-password-without-going-to-apple.html However, they are not 100% clear on al...
Read more

Migrating from Windows to Mac

If you have decided to migrate from Windows to Mac, you will find that there are a few confusing differences. I note the ones that I can think of, below: 1. There are ALTERNATIVE packages to microsoft office installed, namely Apple Pages, Apple Numbers, and Apple Keynote . These replace Word, Excel and Powerpoint, and if you use them you can use the " save as " command to create a word, excel or powerpoint document. This means you do not need to actually buy MS Office, these work just fine. 2. I recommend AVG antivirus be installed . This is mostly so that if you accidentally go onto a bad website with bad software on it, or a fake website, e.g. a "phishing" site, which is trying to trick you into giving your banking credentials, it will warn you. There are almost no viruses or malware for the machine. HOWEVER , there is ONE piece of malware which pretends to be good software, available, and it calls itself MacKeeper. Do NOT install it. AVG complains a lot on W...
Read more