linux删除文件中含有某字符的行

#!/bin/sh
FILENAME=file.txt   # 可换为$1

if [ ! -f file.txt ];then
        echo "$FILENAME no found"
        exit 1
fi
echo -n "INPUT SOME THING: "
read
if [ ! -z "$REPLY" ];then
     INFO=$(grep $REPLY FILENAME)
     if [ ! -z "$INFO" ] ; then
          sed -i -e '/$REPLY/d' FILENAME   #删除只用这行就可以了
     else
          echo "没有指定内容的信息"
          exit 1
     fi
else 
     echo "input some thing"
     exit 1
fi
exit $?