Better than my septem life, that’s for sure
So, the original content is lost forever?
No, but it becomes invisible and inaccessible* as long as the filesystem is mounted over it - see this Stack Exchange question and accepted answer.
The benefits are marginal, for example I can see if a filesystem is mounted by simply typing ll /mnt (ll being an alias of ls -lA) - it comes handy with my system due to how I manage a bunch of virtual machines and their virtual disks, and it’s short and easy to type.
Some programs may refuse to write inside inaccessible directories, even if the root user can always modify regular files and directories as long as the filesystem supports it.
It’s not a matter of security, it’s more of a hint that if I’m trying to create something inside those directories then I’m doing something wrong (like forgetting to mount a filesystem) and “permission denied” errors let me know that I am.
No, directories without anything mounted on them are normal directories - which checks out, since you can mount anything anywhere; unlike Windows volume letters, which only exist when volumes are mounted or detected by the OS.
When you mount a filesystem onto a directory, the OS “replaces” its contents AND permissions with that of the filesystem’s root.
Here’s an example with my setup (hopefully you’re somewhat familiar with Bash and the output of ls -l).
Imagine some random filesystem in /dev/sda1 owned by “user” which only contains a file named “/Hello World.txt”:
$ # List permissions of files in /mnt:
$ # note that none of the directories have read, write nor execute permissions
$ ls -la /mnt
drwxr-xr-x 1 root root 168 May 31 23:13 .
drwxr-xr-x 1 root root 128 May 31 23:14 ..
d--------- 1 root root 0 Aug 1 2020 a/
d--------- 1 root root 0 Feb 11 2022 b/
d--------- 1 root root 0 Aug 11 2021 vdisks/
$ # No read permission on a directory => directory entries cannot be listed
$ ls /mnt/a
cannot open directory '/mnt/a': Permission denied
$ sudo mount /dev/sda1 /mnt/a
$ # List again the permissions in /mnt: the root of /dev/sda1
$ # has rwxr-xr-x (or 755) permissions, which override the 000 of /mnt/a ...
$ ls -la /mnt
drwxr-xr-x 1 root root 168 May 31 23:13 .
drwxr-xr-x 1 root root 128 May 31 23:14 ..
drwxr-xr-x 1 root root 0 Aug 1 2020 a/
d--------- 1 root root 0 Feb 11 2022 b/
d--------- 1 root root 0 Aug 11 2021 vdisks/
$ # ... and its contents can be accessed by the mounted filesystem's owner:
$ ls -la /mnt/a
drwxr-xr-x 1 user user 168 May 31 23:13 .
drwxr-xr-x 1 root root 168 May 31 23:13 ..
-rw-r--r-- 1 user user 0 Jul 4 22:13 'Hello World.txt'
$ find /mnt
/mnt
/mnt/a
/mnt/a/Hello World.txt
find: ‘/mnt/b Permission denied
find: ‘/mnt/vdisks’: Permission denied
Please note that me setting permissions is just extreme pedantry, it’s not necessary at all and barely changes anything and if you’re still getting familiar with how the Linux VFS and its permissions work you can just ignore all of this.
Adding to what the other comment explained:
I use chown 000 so that regular users fail to access a directory when no filesystem is mounted on it; in practice it never happens, because “regular users” = { me }, but I like being pedantic.
As for /mnt, it is supposed to be a single temp. mountpoint, but I use it as the parent directory of multiple mountpoints some of which are just for temporary use.
I didn’t know there was a book adaptation of that movie
I decided to simply create directories within /mnt, chmod 000 them and use them as fixed mountpoints;
for manual temporary mounts I have /mnt/a, /mnt/b, … /mnt/f, but I never needed to use more than two of them at once.
While this setup doesn’t really respect the filesystem hierarchy, I wouldn’t have used /mnt at all if I were constrained by its standard purpose since having one available manual mountpoint seems pretty limiting to me.
Then again, I have 3 physical drives with ~ 10 partitions, plus one removable drive with its own dedicated mountpoint…
This is the 7th time I see a picture of a table like this, I guess this type of furniture is gaining traction
I don’t know your cysec practices so I can’t address the second paragraph, but to answer the first question - this is probably the reason
BECAUSE if we leave too much SPACE between capitalized KEYWORDS they blend TOGETHER, we get BORED and stop reading the SENTENCE
Me, because I cannot understand how people can miss the facetiousness of this meme template with such confidence
Ah yes, the Unum tower’s child
Following the analogy, what if the screwdriver part was bent by 30° and you had to awkwardly turn the tool while keeping it tilted - but there’s also a spring mechanism that attempts to retract the screwdriver you push too hard against the screw?
(all of that for historical reasons, of course)
((or even to discourage you from using the tool?))
Not necessarily.
They’re a basic data structure used everywhere, most notably with command arguments ( $@ ) and can make shell scripts a viable option for many simple tasks if their syntax makes sense and you don’t have to wonder how their expansion works every time you see one being used.
Zsh, because unlike Bash using arrays in Zsh doesn’t make me want to perform percussive maintenance on the nearest Von-Neumann machine
Wh… what do you mean, “originally as a joke”?
III. We’ve Already Seen Extensive Gains From-
When I was younger, I read R.A Salvatore’s classic fantasy novel, The Crystal Shard. There is a scene in it where the young protagonist, Wulfgar, challenges a barbarian chieftain to a duel for control of the clan so that he can lead his people into a war that will save the world. The fight culminates with Wulfgar throwing away his weapon, grabbing the chief’s head with bare hands, and begging the chief to surrender so that he does not need to crush a skull like an egg and become a murderer.
Well this is me. Begging you. To stop lying. I don’t want to crush your skull, I really don’t.
Yeah, but do you know how dangerous a tree is? It will eat you alive without mercy
