So if you run sudo dpkg --configure -a does it finish the upgrade? Another option to try if it will let you sudo apt-get install --fix-missing. To get into recovery mode....
Got this on the Ubuntu wiki here: https://wiki.ubuntu.com/RecoveryMode
Switch on your computer
Wait until the BIOS finishes loading (you will probably see a logo of your computer manufacturer)
The following messages will show up:
Grub loading stage1.5
Grub loading, please wait...
Press ESC to enter the menu
Quickly press the Escape key, which will bring up a boot menu. (If you see the Ubuntu logo, you've
Select the line ending with '(recovery mode)', probably the second line, something like:
Ubuntu, kernel 2.6.17-10-generic (recovery mode)
Press enter and your machine will begin the boot process.
After a few moments, your workstation should display a menu with a number of options. One of the options (you may need to scroll down to the bottom of the list) will be "Drop to root shell prompt".
error while loading shared libraries __vdso_time
– ShaggyInjun Jul 14 '13 at 23:24