2025-04-10 (3 UE): Linux Host System Setup

Overview: User? Home?

User credentials
$ id
uid=1000(jfasch) gid=1000(jfasch) groups=1000(jfasch),10(wheel),104(input) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
Home directory = current working directory
$ pwd
/home/jfasch

Tour Through File System

  • /

    ...
drwxr-xr-x.  21 root root 4300 Apr  7 20:53 dev
drwxr-xr-x.   1 root root 4908 Apr  3 17:17 etc
drwxr-xr-x.   1 root root   26 Jan 15 14:08 home
dr-xr-xr-x. 398 root root    0 Mar 21 16:03 proc
dr-xr-x---.   1 root root  278 Jan 15 14:57 root
dr-xr-xr-x.  13 root root    0 Mar 21 16:03 sys
drwxr-xr-x.   1 root root  168 Jan 15 14:36 usr
...

  • /etc: system configuration

    $ ls -l /etc
... # user and group database
-rw-r--r--. 1 root root 2931 Jan 15 14:08 /etc/passwd
-rw-r--r--. 1 root root 1110 Jan 15 14:08 /etc/group
... # service configuration (sshd ...)
drwxr-xr-x. 1 root root      336 Nov 16 01:00 systemd
...

  • /sys: hardware device tree (and access)a

    $ ls -l /sys/bus/
...
drwxr-xr-x. 4 root root 0 Apr  9 15:02 i2c
drwxr-xr-x. 5 root root 0 Apr  9 15:02 pci
drwxr-xr-x. 4 root root 0 Apr  9 15:02 spi
...

  • /dev: hardware device access

    $ ls -l /dev
... # block devices; eg. solid state disk
brw-rw----.  1 root   disk    259,     0 Mar 21 16:03 nvme0n1
brw-rw----.  1 root   disk    259,     1 Mar 21 16:03 nvme0n1p1
brw-rw----.  1 root   disk    259,     2 Mar 21 16:03 nvme0n1p2
brw-rw----.  1 root   disk    259,     3 Mar 21 16:03 nvme0n1p3
... # hardware; e.g. UARTs
crw-rw----.  1 root   dialout   4,    64 Mar 21 16:03 ttyS0
crw-rw----.  1 root   dialout   4,    65 Mar 21 16:03 ttyS1
... # pseudo devices
crw-rw-rw-.  1 root   root      1,     8 Mar 21 16:03 random
crw-rw-rw-.  1 root   root      1,     5 Mar 21 16:03 zero

  • /home: user home directories

  • /root: root (administrator) home directory

  • /usr: executable code (programs and shared libraries - the system runtime)

  • /boot: bootloader specific, kernel image

Work Environment

  • Work directories in ~/My-Projects/

  • Build directories in ~/My-Builds/

In home directory (/home/jfasch)

$ cd
$ pwd
/home/jfasch

$ mkdir My-{Projects,Builds}

Get Code, Build