Question

bash shell编程--函数调用--帮忙(add 20ps)

#! /bin/bash
rename()
{
ARGS=2
E_BADARGS=85
ONE=1 # For getting singular/plural right (see below).

if [ $# -ne "$ARGS" ]
then
echo "Usage: `basename $0` old-pattern new-pattern"
# As in "rn gif jpg", which renames all gif files in working directory to jpg.
exit $E_BADARGS
fi

number=0 # Keeps track of how many files actually renamed.

for filename in *$1* #Traverse all matching files in directory.
do
if [ -f "$filename" ] # If finds match...
then
fname=`basename $filename` # Strip off path.
n=`echo $fname | sed -e "s/$1/$2/"` # Substitute new for old in filename.
mv $fname $n # Rename.
let "number += 1"
fi
done

if [ "$number" -eq "$ONE" ] # For correct grammar.
then
echo "$number file renamed."
else
echo "$number files renamed."
fi

exit 0
}
while true
read ch
do
case $ch in
rename) rename;;
esac
done
请问运行时怎么才能使rename()发挥作用?
./rename file1.txt file2.txt
没有效果，改变不了文件名呢？（rename后加了$f1 $f2也做不到），请执教！

Answer 1

输入rename即可起作用，不过调用rename时应该带上参数，因为函数中$1和函数外的$1不是一回事。
rename $1 $2;;