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System Sensors

Your system likely has many sensors built in for displaying useful information on internal hardware status. For example, the commands below will help in finding the path to system temperature sensors.

user@host ~ $:sensors -f
Adapter: ISA adapter
Package id 0:  +80.6°F  (high = +176.0°F, crit = +212.0°F)
Core 0:        +73.4°F  (high = +176.0°F, crit = +212.0°F)
Core 1:        +73.4°F  (high = +176.0°F, crit = +212.0°F)
Core 2:        +69.8°F  (high = +176.0°F, crit = +212.0°F)
Core 3:        +68.0°F  (high = +176.0°F, crit = +212.0°F)

Adapter: ACPI interface
temp1:        +82.0°F  (crit = +221.0°F)
temp2:        +85.6°F  (crit = +221.0°F)

Adapter: PCI adapter
GPU core:     +0.97 V  (min =  +0.60 V, max =  +1.27 V)
fan1:         691 RPM
temp1:        +89.6°F  (high = +203.0°F, hyst = +37.4°F)
                       (crit = +221.0°F, hyst = +41.0°F)
                       (emerg = +275.0°F, hyst = +41.0°F)
power1:       36.13 W  (crit = 275.00 mW)

Adapter: ISA adapter
cpu_fan:        0 RPM

We can see that the CPU and GPU temperature sensors are known to our system as coretemp-isa-0000 and nouveau-pci-0100, respectively. Run the command below to list the system path to all connected temperature devices by name, and cross-check these two outputs to gather the needed information for your sensors.

user@host ~ $:for i in /sys/class/hwmon/hwmon*/temp*_input; do echo "$(<$(dirname $i)/name): $(cat ${i%_*}_label 2>/dev/n
ull || echo $(basename ${i%_*})) $(readlink -f $i)"; done

acpitz: temp1 /sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp1_input
acpitz: temp2 /sys/devices/virtual/thermal/thermal_zone0/hwmon0/temp2_input
coretemp: Package id 0 /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp1_input
coretemp: Core 0 /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp2_input
coretemp: Core 1 /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp3_input
coretemp: Core 2 /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp4_input
coretemp: Core 3 /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp5_input
nouveau: temp1 /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/hwmon/hwmon3/temp1_input


When attempting to manage displays, whether its the orientation or enabling / disabling, look to the man pages for xrandr. See the commands below for some examples.

# Output information on displays

# List the output names for displays
xrandr --output

# Move DP-2 to the right of HDMI-1
xrandr --output DP-2 --right-of HDMI-1

#### Timezone

To see date / time, run `date`

To adjust local TZ settings, run `tzselect`. Pay attention to the final output of this tool as it will explain how to make your change permenant. For me, I had to add the following to the end of my `~/.profile` :

TZ='America/New_York'; export TZ


Some useful commands to find information on memory usage -

# Output various memory details
cat /proc/meminfo
#Can be used with grep, awk, etc for more specific output..
# ex) Show MiB of memory available
grep -w MemAvailable: /proc/meminfo | awk '{print $2 / 1024 "MiB"}'

Input Devices

Run the following to get information on input devices attached to the machine -

# In the output shown below, my keyboard is AT Translated Set 2 keyboard
xinput list
# Example output:
⎡ Virtual core pointer                          id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Elan Touchpad                             id=10   [slave  pointer  (2)]
⎣ Virtual core keyboard                         id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Power Button                              id=6    [slave  keyboard (3)]
    ↳ Power Button                              id=7    [slave  keyboard (3)]
    ↳ Sleep Button                              id=8    [slave  keyboard (3)]
    ↳ TOSHIBA Web Camera - HD: TOSHIB           id=9    [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=11   [slave  keyboard (3)] 

# Test the device.. 
xinput test "AT Translated Set 2 keyboard"
# Example output:
key release 36
key press   40
dkey release 40
key press   50
key release 50
# The output above shows me pressing / releasing keys in real time.
# Exit with CTRL-C

Power Supplies / AC Adapters

# List power supplies, AC adapters -
ls -l /sys/class/power_supply/
# Example output...
lrwxrwxrwx 1 root root 0 Mar 23 23:02 AC -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:00/PNP0C09:00/ACPI0003:00/power_supply/AC
lrwxrwxrwx 1 root root 0 Mar 23 23:02 BAT0 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:00/PNP0C09:00/PNP0C0A:00/power_supply/BAT0
# Above, my battery is seen as BAT0, my AC port for charging is AC