while;for

while ; for 

while true;do ... done ; cat filename |while line;do...done ; while read line;do...done<./filename

for i in nums;do ... done 

注意：for 在逐行的读文件时是以空格作分隔符的， 如 aaa bbb 同行会扫出两个元素

while read LINE

do echo "begin to restore file " $LINE ext3grep /dev/vgdata/LogVol00 --restore-file $LINE if [ $? != 0 ] then echo "restore failed, exit" # exit 1 fi done < ./mysqltbname.txt