echo $RANDOM | cksum | cut -c 1-8 openssl rand -base64 4 | cksum | cut -c 1-8 date +%N | cut -c 1-8
echo "fdsahjgkdhsajglhdjsaga" &>/dev/null
#grep -v 不顯示該條件,-c統計查找條數。 grep -vc grep
awk '{print"輸出:'"$var"'",$1}'
# -e 爲拓展 echo -e "\n"