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Otázka
Superuzdro čítačka fangxing chce vedieť, prečo by Linux umožnil užívateľom odstrániť koreňový adresár:
When I installed Linux on my computer for the first time, I always liked to use root because I did not need to add sudo and enter my password every time I executed a command that needed root level permissions.
One day, I just wanted to remove a directory and ran rm -rf /, which “broke” my system. I have been wondering why Linux’s designers did not block such a dangerous command from being run so easily.
Prečo Linux umožňuje užívateľom odstrániť koreňový adresár?
Odpoveď
Sponzor SuperUser Ben N má odpoveď pre nás:
Why should it block you from doing whatever you want with your own computer? Logging in as root or using sudo is literally saying to the machine, “I know what I am doing.” Preventing people from doing dubious things usually also prevents them from doing clever things (as expressed by Raymond Chen).
Besides, there is one singularly good reason to allow a user to torch the root directory: decommissioning a computer by completely erasing the operating system and file system. (Danger! On some UEFI systems, rm -rf / can brick the physical machine too.) It is also a reasonable thing to do inside a chroot jail.
Apparently, people accidentally ran the command so much that a safety feature was added. rm -rf / does nothing on most systems unless –no-preserve-root is also supplied, and there is no way that you can type that by accident. That also helps guard against poorly-written but well-intentioned shell scripts.
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