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linuxwifiiwconfig

Wireless wlan0 management

I implemented a function in order to connect my device to an access point which contains :

iw mlan0 connect $SSID
udhcpc -i mlan0
while : ; do
    echo "Pausing until connection established"
    mlan0_ip=`/sbin/ifconfig mlan0 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'`
    if [ -z "$mlan0_ip" ]
    then            
        sleep 1
    else
        break
    fi
done

I don't understand why the iw mlan0 connect $SSID command keep the prompt. Indeed, it is blocked on 

[ 6231.764960] wlan: SCAN COMPLETED: scanned AP count=9
[ 6231.798636] wlan: Connected to bssid 1a:XX:XX:XX:52:66 successfully
[ 6231.808511] IPv6: ADDRCONF(NETDEV_CHANGE): mlan0: link becomes ready
udhcpc (v1.22.1) started
Sending discover...
Sending discover...
Sending discover...
[ 6241.126472] ADDBA RSP: Failed(1a:XX:XX:XX:52:66 tid=6)
Sending discover...
[ 6264.263093] ADDBA RSP: Failed(1a:XX:XX:XX:52:66 tid=6)
Sending select for 192.168.50.33...
[ 6264.497054] ADDBA RSP: Failed(1a:XX:XX:XX:52:66 tid=6)
Lease of 192.168.50.33 obtained, lease time 43200

Basically I never enter into the while loop.. I would like to execute some others command after network configuration

Solution

  • Try putting an ampersand at the end of the command, it will run in background allowing the next command to execute.

    iw mlan0 connect $SSID &
udhcpc -i mlan0
while : ; do
    echo "Pausing until connection established"
    mlan0_ip=`/sbin/ifconfig mlan0 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'`
    if [ -z "$mlan0_ip" ]
    then            
        sleep 1
    else
        break
    fi
done

    But I can see in the log a message of udhcpd, and then the problem will be it, because if iw started and udhpcd started but the loop is not starting, you can try to put a ampersand also on the second command.

    udhcpc -i mlan0 &