if you have one, and try repairing that disk again.
Disk Utility cannot repair a disk that it is booted from.
You have not mentioned what model/type of Mac you have but from your trouble shooting efforts I am guessing an iMac, but not a recent one.
Usually, when a drive gets that full, you get a warning, did you ever get one?
It is also possible that there is a huge temporary file sitting on your drive which was produced by the failed effort to read a pdf file.
If you are unable to access the drive then it could be that your only recourse is to re-install OS X and start again.
P
OK. I'll preface this by saying I'm not super computer savvy, but...
It all started when I tried viewing a .pdf in Safari. Got the rainbow wheel...it never loaded. Couldn't even quit the other apps that were running. Couldn't open Force Quit. So after 30 min, I shut down with the power button for 10 seconds. Then restarted with the power button and got the login screen with 4 users entirely too fast. When trying to log in to any of them, I enter the password and then grey screen with apple and spinning dial. Forever.
So I keep shutting off with the power button and the screen clicks and goes black and the fan stops. When restarting, I hear the chik-chik and then the 4 users again. I've tried this with the power cord, without, and after following instructions for SMC(?) shutdown. No difference.
I have tried turning on with the R button and got to disk utility - verified and repaired (seemed logical enough). There was nothing wrong.
Then got "info" on the HD and found out that of the 499GB, I only have 16 MB left. I recently added my work email to Mail and I think that may be the memory issue.
When trying to start with Shift key (safe?), nothing different happens. When trying to start with Command-S (single user mode?), I get a flash of a black screen, and them the 4 users again. No opportunity to type on the black screen.
I'm more than willing to delete all the music and photos in iTunes Library and iPhoto library, but don't know how to get to those files. (They are backed up elsewhere).
I don't think I have a recent Time Capsule backup (more than 3-4 weeks ago).
HELP!

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