if 文 sample if [ $# -ne 1 ];then echo "Usage: $0 [123]"; exit 1; fi if [ $1 -eq 1 ];then echo "You are number#1."; elif [ $1 -eq 2 ];then echo "You are number#2."; elif [ $1 -eq 3 ];then echo "You are number#3."; else echo "Invalid argume…