Some commands to find out listening ports

net_listen.sh

# find all listening ports
cat /proc/net/tcp  | awk '$4 == "0A" {print $2}' | awk -F: '{print strtonum("0x"$2)}'

# find all listening ports and print their inodes as well
cat /proc/net/tcp  | awk '$4 == "0A" {print $10" "$2}' | tr : ' ' | awk '{printf "%d %d\n", strtonum("0x"$3), $1}'

# find all socket for PID and print their inodes
find -L /proc/<PID>/fd -type s -printf "%i\n"

# find listening ports for by PID
ss -ltnp4 | grep 26532 | tr -dc '0-9 \n'

# find all Listening ports and their PID by proccess name
ss -ltnp4 | grep memcached | tr , ' ' | tr -dc '0-9 \n' | awk '{print $3" "$4}'