It's not so much assuming you've got no idea what's in the file, as it is, *NOT* assuming that you will always know what's in it. With regard to security, the assumption is always that a file or other input could contain malicious data. There's no way to be certain of what the file contains, so you code defensively. Human error, malice, even a problem with the file system, could conceivably cause the input file to contain strings that would be devastating if executed. Check out an amusing take on this issue Can't Happen or /*NOTREACHED*/ or Real Programs Dump Core. It's somewhat dated, but still has many good points. Plus, it's fun.

In reply to Re^4: Reading from txt makes variables literal? by spiritway
in thread Reading from txt makes variables literal? by Anonymous Monk

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