First, mount the dmg image : sudo hdiutil attach <image>.dmg
The image will be mounted to /Volumes/<image>. Mine contained a package which i installed with: sudo installer -package /Volumes/<image>/<image>.pkg -target /
Finally unmount the image: sudo hdiutil detach /Volumes/<image>.
If you want to do it from the command line, you can use hdiutil like so:
hdiutil create -volname WhatYouWantTheDiskToBeNamed -srcfolder /path/to/the/folder/you/want/to/create -ov -format UDZO name.dmg
Man hdiutil for more details.
The error message is pretty unclear, but one reason might be that you are not connected to the power outlet. Compacting a disk image might be a long and intensive task, and sometimes the OS denies it when you are running on battery to avoid any risk of data loss.
If you are positive that you have enough battery power to complete the task, you may overrun ...
The problem appears to happen when you unmount the image using umount.
Remount the image (either using hdiutil attach or just double click the image) and use the command hdiutil detach it again. This will unmount and eject the image.
hdiutil detach /Volumes/<your image>
DMGs have a few key features which make them superior to plain old zips
They’re a full file system (meaning they can store file permissions, have custom folder backgrounds, etc)
They support “mandatory” EULAs before mounting which is nice for legal stuff
Provide a more reliable execution environment. If you have to do absolute path stuff for installation (...
You can use hdiutil to convert from .dmg to .iso directly:
$ hdiutil makehybrid -iso -joliet -o [filename].iso [filename].dmg
Renaming .cdr to .iso is bad advice! An .iso has a slightly different format that allows PC users to play the DVD as well. A renamed file will work on macOS, but NOT on a PC.
If you have a .cdr and want to convert it to an .iso, ...
A .dmg file is kind of like an USB stick in a file and can be handled more or less the same way. To install from a .dmg file you usually do the following:
double click the .dmg to make its content available (name will show up in the Finder sidebar), usually a window opens showing the content as well
drag the application from the .dmg window into /...
Download on the first machine.
When complete, the Installer will auto-launch.
The Installer is in /Applications/ and has the name Install macOS Sierra. [BTW it's not a .dmg, but an .app file]
Copy it to a safe place; after install it will be auto-deleted from Applications.
The copy can then be used on any other machine. Drop into the ...
.dmg files are disk images, similar to an .iso file.
You can think of them like a virtual CD. You put it into the CD drive (mount it), and its contents appear on your computer.
When used for software downloads, they are simply a way to bundle up files, like in a ZIP archive. Their advantage is that it's possible to customize the design (e.g. Finder window ...
An application on a Mac is just a folder full of files with a .app extension. However, macOS hides this fact from you and displays the folder as a file with an icon. Now when you download something it's very uncomfortable to download multiple separate folders (without a download manager). Therefore this "App Folder" has to be put inside a single file somehow....
Yes, Disk Utility can do this. Use Convert then select your dmg file. In the Save As dialog that follows, select DVD/CD master. Disk Utility will insist on saving the new ISO as a .cdr file, but it is really an ISO. You can rename it to .iso in the Finder, if you like.
At http://osxdaily.com/2012/07/18/convert-dmg-to-cdr-or-iso-with-disk-utility/ there are ...
Data on DMG image can be checked for integrity with Disk utility. You can make it mandatory for the user to agree to license before mounting dmg. It could be locked from modification. You can easily add hidden files and folders on DMG. You can make background image. You can make it safe from stripping during transit through non-metadata aware file systems ...
I've been interested in this question since Nov 2012 and even set up a FreeNAS VM to reproduce the issue.
I eventually gave up but since the question has been resuscitated I will share what I found out back then and in the last hours (luckily I didn't delete the VM) and what I think the cause for this issue is. I have also found a workaround.
I was experiencing this problem after downloading High Sierra to fix a friend's Mac. I found Rick's solution worked for me, but I've added a few more steps.
Click the symbol in the Menu bar.
Hold down Command + R to boot into Recovery Mode.
Type csrutil disable. This will disable SIP.
Press Return or Enter ...
.dmg is not an app, it is a disk image. If you double-click the file, it should mount a virtual disk in the Finder. From there, you will be able to drag and drop the image into your applications folder.
Since you don't have admin rights on the computer you're using, you'll need to drag it into your user Applications folder (/Users/yourname/Applications/, ...
A lot of applications (bundles) for OS X don't need an installer in contrary to almost all Windows apps. They are distributed inside an .dmg.
To properly "install" them just open the .dmg and copy the app file to /Applications or /Applications/Utilities. A lot of images already contain a soft link to the Applications folder to be more convenient for the ...
I had the same problem, and managed to open .dmg files by going into Disk Utility>File>Open Disk Image. Once opened in Disk Utility, Double Click (Right Click) the icon and click show in Finder. Then I could install what I wanted! Hop it works for you!
A DMG file (Apple Disk Image) is a disk image file that is mounted as a volume, just like a physical disk. They can be password protected and compressed (like ZIPs), and are usually used for packaging and downloading Mac software (amongst other things).
DMGs are exclusively an Apple file format (though can be opened as read-only on Windows computers with ...
The /Applications folder is just a convenient place to store all of your applications. You can theoretically store them anywhere. Some software (such as Butler) will automatically search for applications in these standard locations, so if you store them elsewhere (such as /Users/Shared/Applications) such software won't find them by default.
Generally there ...
An article written by someone else who did that:
The author did get his cracked, but had to borrow a supercomputer to do so even after he got custom software designed to use partial knowledge of the password he had chosen.
It shows how hard a general cracking effort would be, but ...
It doesn't matter what type the DMG is as VMware Fusion cannot install OS X Yosemite by booting it or even booting the Install OS X Yosemite.app downloaded from Apple as that's not how it works in VMware Fusion. VMware Fusion must first make an Installer Image from the Install OS X Yosemite.app and install from the Image it creates.
Have a look at: ...
Option 1: Disk Utility
In Disk Utility: select the image in the sidebar, then File → Change Password...
(You must unmount the image before you can reset it).
Option 2: Terminal
hdiutil chpass <image>
More info: man hdiutil
One possible reason could be that Safari by default automatically mounts DMG files, and that a Finder window would pop up with the contents. In turn the DMG folder could be styled with for example a background image. I assume that could be considered more user-friendly than having to look in your Downloads folder for an installer, but I agree it's pretty ...
I have an external hard drive with several installers on it. All you need to do is make several partitions, each large enough for the disc you're imaging. (My drive has 10.4 Tiger PPC, 10.5 Leopard PPC, 10.5 Leopard Intel, and 1.6 Snow Leopard on it, and I have a Lion USB flash drive.)
I made the images using Disk Utility's Restore feature. Select the ...