UNIX Shell循环控制—while

while循环，语法如下：while command
do
Statement（s） to be executed if command is true
donecommand可以是一个判断，也可以是一个命令，如读取文件等。当command条件为真，则执行循环中的语句块，否则直接退出循环。实例1、简单的while循环打印从0到10的数据：pg while1.sh
#！/bin/ksh
i=0
while [ $i -le 10 ]
do
echo $i
i=`expr $i + 1`
done
#EOF执行脚本：sh while1.sh
0
1
2
3
4
5
6
7
8
9
10实例2、我想将当前目录下文件名包含if的文件全部移动到iftest文件夹下面。这里借助于一个临时文件temp.txt，创建之后，保存从当前文件夹下中查询到的文件；用完之后，将其删除。pg mvfile.sh
#！/bin/ksh
echo "moving all file which contain word if to directory iftest"# create temporary file temp.txt
if [ -f temp.txt ]; then
"" > temp.txt
echo "clearing temp.txt file successful"
else
touch temp.txt
echo "making file temp.txt successfull"
fi# writing file temp.txt with file contain word if
ls -l | grep "^-.*" | sed -n "/if/"p | awk "{print $9}" > temp.txt# moving file to directory iftest
while read LINE
do
mv $LINE ./iftest
done < temp.txt# droping the temporary file after moving
echo "moving file with if successfull"
if rm -f temp.txt > /dev/null 2>&1; then
echo "removing file temp.txt successful"
fi
#EOF执行此脚本之前，当前目录下文件如下：.../shell>lf
calculator.sh ifcp2.sh ifroot.sh param.sh
child.sh* ifdirec.sh ifset.sh profile.sh
data.file ifeditor.sh iftest/ test/
elif.sh ifelif.sh iftest2.sh testdirec/
env_variable ifels.sh iftst.sh* test1/
father.sh* ifinteractive.sh ifwr.sh tst/
grepif.sh ifmkdir.sh if1.sh* welcome.sh
grepstr.sh ifmkdir2.sh if2.sh 125017.sh
ifcounter.sh ifparam.sh log.txt
ifcp.sh ifpwd.sh name.txt执行之后，包含if的文件全部被移动到iftest目录下：.../shell/iftest>lf
elif.sh ifeditor.sh ifparam.sh ifwr.sh
grepif.sh ifelif.sh ifpwd.sh if1.sh*
ifcounter.sh ifels.sh ifroot.sh if2.sh
ifcp.sh ifinteractive.sh ifset.sh
ifcp2.sh ifmkdir.sh iftest2.sh
ifdirec.sh ifmkdir2.sh iftst.sh*--the end--