shell script for enabling sniffer mode in wire shark

shell script for enabling sniffer mode in wire shark
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#! /bin/sh
sudo ifconfig wlan8 down
sudo iwconfig wlan8 mode monitor
echo "Enter Ch no. "
read ch_no
sudo iwconfig wlan8 ch $ch_no
#echo $ch_no
sudo ifconfig wlan8 up
sudo wireshark
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