GNU+Linux command memo

WiFi txpower

Save some battery on WiFi, when you are sufficiently near from the hotspot.

Diminuer la puissance d’émission du WiFi pour économiser de la batterie quand la borne est suffisamment proche.

- via iwconfig

# iwconfig wlan0 txpower 5mW  (1) (2)
1 Instead of 130mW with a stock Intel WiFi card. It corresponds to 7dBm instead of 22dBm.
2 You may adjust the mW value based on your distance from the hotspot and the reported bit rate of the WiFi connexion. If the bit rate falls, you should set a higher wattage.

- via iw

# iw dev wlan0 set txpower fixed 700 (1)
1 Using the recent wireless drivers Linux kernel interface (work in progress since 2015). Unit is mBm (100 mBm = 1 dBm).

To run the command at startup

Instructions are here : Run a command at startup.