lfs

A linux utility listing your filesystems.

Besides traditional columns, the disk column helps you identify your "disk" (or the mapping standing between your filesystem and the physical device) :

• remov : a removable device (such as an USB key)
• HDD : a rotational disk
• SSD : a solid state storage device
• RAM : an in-memory device (such as zram)
• LVM : a device mapped to one or several disks using LVM
• crypt : a crypted disk

All sizes are normally based on the current SI recommendations (1M is one million bytes) but can be changed with --units binary (then 1M is 1,048,576 bytes).

Installation

Precompiled binary

You can download it from https://github.com/Canop/lfs/releases

From source

You need the Rust tool chain.

cargo install lfs

Arch Linux

lfs can be installed from the community repository:

pacman -S lfs

Usage

lfs

All filesystems

By default, lfs only shows mount points backed by normal block devices, which are usually the "storage" filesystems you're interested into.

To show them all, use

lfs -a

JSON

To get the output as JSON, do lfs -j or lfs -a -j.

Here's an example output, with comments:

[
  { // one entry per filesystem
    "dev": { // device id, commonly represented as 8:1
      "major": 8,
      "minor": 1
    },
    "disk": {
      "crypted": false,
      "ram": false, // true for memory disks
      "removable": false,
      "rotational": false, // true for HDD
      "type": "SSD" // human readable disk type
    },
    "fs": "/dev/sda1",
    "fs-label": null, // not null when the fs is labelled
    "fs-type": "ext4",
    "id": 26, // filesystem id
    "mount-point": "/",
    "stats": {
      "available": "82G", // human readable available space
      "bavail": 19973841, // number of free blocks for underprivileged users
      "bfree": 23000170, // number of free blocks
      "blocks": 59233748, // total number of blocks
      "bsize": 4096, // size of a block, in bytes
      "favail": 14088395, // number of free inodes for underprivileged users
      "ffree": 14088395, // number of free inodes
      "files": 15114240, // total number of inodes
      "size": "243G", // disk size, for humans, SI unit
      "used": "161G", // used space, SI unit
      "used-percent": "66%"
    }
  }
]

Find the filesystem you're interested into

You may pass a path to have only the relevant device shown. For example:

Show labels

Labels aren't frequently defined, or useful, so they're not displayed by default.

Use --labels or -l to display them in the table:

Show inodes

To display inodes use, use --inodes or -i:

Other options

Use lfs --help to list the other arguments.

Internals

If you want to display the same data in your Rust application, have a look at the lfs-core crate.