How to exit Minecraft single player without saving?

Question

I was building my factory in single player Tekkit wearing my nice gem armor using a red morningstar to mine out an area below it to place the machines. I quickly switched the hammer mode from 3x3 to single block to work on some details... or that was what would have happened if I actually had it selected.

What the key press actually did was use the offensive power of my gem armor and produce a big explosion at my current position which destroyed half of my machines and most of the walls, leaving an unsightly crater in the ground.

I know the map state got saved just a minute or so before that happened.

Next time that happens, is there any way to quickly leave the game without saving the new mapstate?

Answer 1

The world saves occasionally, and also whenever you pause (with escape), but if you free your mouse by opening your inventory and close the window there is a chance the world was not saved and you can revert some changes.

However, this will always save your inventory, so you cannot use this to reclaim lost items.

Answer 2

I had a similar problem once, I went exploring the world and didn't find back to my base. AFAIK, minecraft saves changes every x seconds.

What you can do is backing up your saves folder (Located under your home directory .minecraft\saves\<name of your world>) every now and then (or before a dangerous trip).

When you die or loose something in lava, just exit the game and copy the savegame back over the original files.

This way you can keep as many saved states as you like.

Answer 3

Quickly do Alt+F4 to close the window. Alternatively, you can press Alt to free your mouse, and hit the close window button. If you are in full-screen mode, you can press Alt to free your mouse, do Alt+Tab to switch the window, right-click on Minecraft, and press close window. Make backups every now and then so that if it does save, you can try again.