Example:
This is absolutely wrong. To what does a point? You don't know the answer to that question and neither do I. This is a prime example of overwriting memory. When char *a is declared, it points to a random location in memory. In computer jargon, we can say that a points to garbage as soon as it is declared. However, one programmer's garbage may be anther's treasure. As was stated in prior chapters, when you overwrite computer memory, you're involved in a game of logic Russian roulette, and the outcome can be almost anything. The program may work or seem to work perfectly. If this is true, then the hammer fell on an empty chamber. The computer could have locked up, or worse, returned inaccurate information. Bingo! The hammer fell on a loaded chamber. While such occurrences are rarely disastrous when using small-memory model compilers, large-memory model versions may allow a memory overwrite to trip a few interrupts and, maybe, erase the file allocation table (FAT) on your hard drive. Double bingo! You've just rendered your entire hard disk useless!
Is that an idiom? What exactly does it mean? What kind of chamber are they talking about?
Best Answer
It is using gun terminology as a metaphor for luck. In a gun, the slots where the bullets go are called "chambers" and the thing that hits the bullet to make it fire is called a "hammer".
The game Russian Roulette is a game of chance that uses a revolver with only one bullet loaded which is then spun randomly and fired. If the person is lucky, there will not be a bullet in the chamber it landed on (it will be empty), if they are unlucky there will be a bullet there (it will be loaded).
When you fire a gun, pulling the trigger causes the hammer to "fall" against the bullet in the chamber, which fires it. So saying "the hammer fell on an empty chamber" means you got lucky; saying "the hammer fell on a loaded chamber" means you got unlucky.