shell实例(十八) ----look,tr命令

1.检查列表中单词的正确性

#! /bin/sh
file=11-10.sh
i=0
while [ "$word" != "exit 0" ]
do
let " i += 1"
read word
echo "/"word/" is "$word"."
look $word > /dev/null
lookup=$?
if [ "$lookup" -eq 0 ]
then
echo "/"$word/" is valid."
else
echo "/"$word/" is invalid"
fi
done < "$file"

echo
exit 0

2.将当前目录下的所有文全部转换为小写

#! /bin/sh
for filename in *
do
fname=`basename $filename`
n=`echo $fname | tr A-Z a-z`
if [ "$fname" != "$n" ]
then
mv $fname $n
fi
done

exit $?

3.fmt进行折行

#! /bin/sh
WIDTH=20
b=`cat /usr/local/yjg/11-11.sh`
echo $b | fmt -w $WIDTH
exit 0

4.