awk 'function hextodec(str,ret,n,i,k,c){ ret = 0 n = length(str) for (i = 1; i <= n; i++) { c = tolower(substr(str, i, 1)) k = index("123456789abcdef", c) ret = ret * 16 + k } return ret } function getIP(str,ret){ ret=hextodec(substr(str,index(str,":")-2,2)); for (i=5; i>0; i-=2) { ret = ret"."hextodec(substr(str,i,2)) } ret = ret":"hextodec(substr(str,index(str,":")+1,4)) return ret } NR > 1 {{if(NR==2)print "Local - Remote";local=getIP($2);remote=getIP($3)}{print local" - "remote}}' /proc/net/tcp