help!! completely removing a disk image / volumes / undoing partitions (using unix?)

[grrraeme]

hi there,

a while ago i made two disk images to copy dvds, both are about 4.7GB. i don`t need them anymore, so i want to get rid of them completely and have the space returned to my Macintosh HD volume.

i used disk utility to eject the two images, and it took lots of trying, but they seem to have dissapeared finally... but still, the 10GB of space has not returned to my HD!

i guessed the disk images were still lurking somewhere, so i quickly read the Terminal manual, and booted UNIX for the first time!

i used UNIX to list the contents of my mac, and found the disk images lurking in the /Volumes directory...

in the /Volumes directory i have:

DISK_IMAGE1.cdr DISK_IMAGE2.img Macintosh HD

i tried to use the RM command to get rid of the images ( rm /Volumes/DISK_IMG1.cdr ), and it asked for confrmation... actually, i wasn`t sure how to answer so i tried `y` for yes, and got some message about the images being `read only`

have i somehow screwed up and these images are actually partitions? i still don`t quite understand the whole disk image / partitions thing...



SO! what i want to know is how to delete these images, and get that 10GB back to my Macintosh HD volume!!!

i don`t understand a lot of computer talk, so, if someone can help me with a simple explanation, or just give me a list of commands to type to do the job, i would really, really, appreciate it! thanks!!

by the way, i have a ibook G4! and what a great machine it is!

 

[frankblundt]

In Finder > Go > Go To Folder - type /Volumes
and it should open a window with the offending volumes in it, which you ought to be able to trash (although you may need to put in an admin user/password)

 

[ElectricSheep]

just fyi, when you booted into 'unix', you were actually booting into something called 'single user mode'.

When you boot into single user mode, your startup disk is mounted as read only, meaning you cannot make any changes to it. You can't alter files, make new files, or delete files. You have to first explicitly unmount and remount your startup disk as read/write.

That's why you couldn't remove the disk images.

In the future, you don't have to boot into single user mode to access a command line. Just open the Terminal.app located in the Utilities folder.

 

[grrraeme]

You have to first explicitly unmount and remount your startup disk as read/write...

...In the future, you don't have to boot into single user mode to access a command line. Just open the Terminal.app located in the Utilities folder.

thanks for the tip!
1. so, how do i ummount and remount my startup disk as read/write?
2. also, i opened terminal at first, but when i am in terminal i am in my own user directory (grrrraeme`s ibook g4), which is of course stored on the macintosh hd. so i can`t find the /Volumes directory, or access the disk images... how do i move from my user directory to the main macintosh hd?

sorry i don`t know all the correct technical terms for things!

if you can figure out where i am going wrong, and perhaps just give me a list of commands to type in and do the job, i would really appreciate it!!!!

(on a personal note... it`s funny, like most people i always just use os x and have no idea of the hidden workings behind the computer. discovering terminal and unix etc for the first time was a complete eye opener! i can`t wait to find out more about it and how to use it properly, it feels like cutting out a middle man and going straight to the heart of the computer... if that makes sense!! very exciting anyway!!)

 

[frankblundt]

In Finder > Go > Go To Folder - type /Volumes
and it should open a window with the offending volumes in it, which you ought to be able to trash)

the "/" part of it tells finder to ignore where you are and go to the root directory (the HD). You can browse the HD directly, but Volumes (and a bunch of other folders are hidden, so you need to use the Go menu to get there. Once there however it opens just like any other directory. This is a non-Terminal way of course..

in Terminal type cd /Volumes

 

[frankblundt]

There are utilities like Xupport which will let you alter many of the hidden and locked features of OS X, as well as do things like seeing hidden files, dumping caches, swap files etc and general maintenence - but be careful, X is locked up the way it is for a reason: protecting you from yourself!

There's a Terminal tutorial here, courtesy of Google, but i can't speak for its usefulness.

 

[ElectricSheep]

thanks for the tip!
1. so, how do i ummount and remount my startup disk as read/write?
2. also, i opened terminal at first, but when i am in terminal i am in my own user directory (grrrraeme`s ibook g4), which is of course stored on the macintosh hd. so i can`t find the /Volumes directory, or access the disk images... how do i move from my user directory to the main macintosh hd?

sorry i don`t know all the correct technical terms for things!

if you can figure out where i am going wrong, and perhaps just give me a list of commands to type in and do the job, i would really appreciate it!!!!

(on a personal note... it`s funny, like most people i always just use os x and have no idea of the hidden workings behind the computer. discovering terminal and unix etc for the first time was a complete eye opener! i can`t wait to find out more about it and how to use it properly, it feels like cutting out a middle man and going straight to the heart of the computer... if that makes sense!! very exciting anyway!!)

If my memory serves me (its been a bit since booting into single user mode), the command /sbin/mount -uw / should do the trick to remount your disk as read/write when in Single User Mode.

As for getting started with the Terminal, you should understand first that the Terminal.app is running a shell, the command-line driven program that you interact with--typing in commands and reading output. The default shell in MacOS X is called 'bash', so if you go googling for tutorials, it would be a good idea to keep that in mind. There are other 'shells' that can be run, but the basic set of commands that you use remain the same. There are just some little nuances that make one shell preferable to one versus another.

•This is a basic Linux Terminal/Bash tutorial. Yes, its for Linux, but the same concepts apply to the MacOS X terminal/shell.
•A basic unix shell tutorial
•Another unix basics tutorial

Just be very careful when working in the shell. The shell is a powerful tool, especially if you have administrative privileges on your account. its a good idea to understand what a command does before executing it. If you aren't absolutely sure, don't execute it!

 

[grrraeme]

thank you!

i just wanted to say thanks for all the help and advice!

i had been frustrated over those disk images for some time, but could find no help anywhere for what seemed like such a simple task. i`d even asked other people, and had a message on the forums before, but no luck!

i simply did the Go > Go To option, and got my 10GB back in a matter of seconds!! i can`t believe it was so easy!!

i`m gonna start reading up about terminal / unix / bash etc in my spare time, but i won`t jump into fiddling with computer without knowing what i`m doing.

sometimes i find mac documentation is designed specifically for beginners, and of course experts know exactly what to do, so those of us in the middle ground are left kind of puzzled... how do we do more complicated things when the mac help and guides only cover the most basic tasks, and sometimes omits those fairly easy tasks that many users will never know exist? if that makes any sense...

thanks anyway!