Check if LAN is plugged

Question

i want to check if the LAN cable is plugged in on a linux system, is there any file in /sys or /proc that i can check (i would like to do it in C)?

Possibly see http://stackoverflow.com/questions/4231507/how-to-check-ethernet-in-linux — Stecman, Sep 08 '12 at 09:44
I just posted a solution @ http://stackoverflow.com/questions/4231507/how-to-check-ethernet-in-linux. Maybe you could use the same. — loxxy, Sep 08 '12 at 10:51

score 5 · Answer 1 · answered Sep 08 '12 at 09:51

5

To check if a cable is plugged you can look in /sys/class/net/

For ex. for eth0 connection:

$ grep "" /sys/class/net/eth0/*
/sys/class/net/eth0/carrier:0
/sys/class/net/eth0/operstate:down

As you can see, cable isn't plugged. if it was plugged i was getting:

/sys/class/net/eth0/carrier:1
/sys/class/net/eth0/operstate:up

answered Sep 08 '12 at 09:51

Ddorda

score 2 · Answer 2 · answered Sep 08 '12 at 09:43

2

Run the ifconfig command which will show all the interfaces connected.

answered Sep 08 '12 at 09:43

P.P

2 Answers2