sed コマンド

# echo "naoki(27)" | sed -e "s/^.*(\(.*\))/\1/"  
27  

# echo "naoki(27)" | sed -e "s/^\(.*\).*(.*).*$/\1/g"  
naoki  

# echo "yamada(27)tarou(29)" | sed -e "s/^.*(.*).*(\(.*\))/\1/g"  
29  

# echo "yamada(27)tarou(29)" | sed -e "s/^\(.*\)(.*).*(.*)/\1/g"  
yamada  

# echo "yamada(27)tarou(29)" | sed -e "s/^.*(\(.*\))\(.*\)(.*)/\2 not \1/g"  
tarou not 27  

# echo "Received: from iidmxi01.alpha-prm.jp ([157.205.203.72])" | sed -e "s/.*\[\(.*\)\].*$/\1/g"  
157.205.203.72