Unexpected behaviour with :disksup.get_disk_info

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1

I am probably holding a piece of Erlang wrong but this was unexpected.

Screenshot_20241003_114033
Screenshot_20241003_1140331132Ă—634 66.9 KB

Any clues?

2

What if you add slash at the end, i.e. /root/ ?

3

Mine works, but I had to do :disksup.start_link before using it as I got the warning:

12:42:54.797 [warning] OS_MON (:disksup) called by #PID<0.110.0>, not started

1 Like
4 
iex(8)> :disksup.get_disk_info()
[
  {~c"/", 488878112, 358518096, 23},
  {~c"/dev", 4096, 4096, 0},
  {~c"/dev/shm", 16388668, 16193968, 2},
  {~c"/sys/firmware/efi/efivars", 128, 97, 22},
  {~c"/run", 6555468, 6553344, 1},
  {~c"/tmp", 16388672, 16303136, 1},
  {~c"/boot", 1684592, 1242612, 22},
  {~c"/boot/efi", 523248, 482132, 8},
  {~c"/run/user/1000", 3277732, 3277576, 1}
]
iex(9)> :disksup.get_disk_info(~c"/")
[{~c"/", 488878112, 358518060, 23}]
iex(10)> :disksup.get_disk_info(~c"/run/user/100")
[{~c"/run/user/100", 0, 0, 0}]
iex(11)> :disksup.get_disk_info(~c"/run/user/100/")
[{~c"/run/user/100/", 0, 0, 0}]

Mine does not, with slash or not at the end.

5

Hmmm, what the. Can you try starting iex as root?

6

no, can’t now actually. But it works for some mount points, not for the others. I could get the stats for /boot for example.

7

You actually have a typo:

Should be ~c"/run/user/1000". This is expected behavior as specified per documentation:

Returns [{Path,0,0,0}] if the Path is invalid or space can’t be determined. Returns [{“none”,0,0,0}] if disksup is not available.

8

lmao okay you’re right, I brought nothing to the conversation