CheckNo=`expr $# % 2`
    if [ $CheckNo -ne 0 ]
    then
            echo "Enter Even Number Of Arguments."else
            cnt=1
            while [ $cnt -lt $# ]
            do
                    cp $1 $2
                    shift
                    shift
                    cnt=`expr $cnt + 2`
            done
    fi

--------------------------------------------------------------------------------

output:
$ sh29 detail.txt temp

$ cat detail.txt
NAME : YAGNIK VIDYADHAR
AGE  : 22
ADDR : VASNA.

$ cat temp
NAME : YAGNIK VIDYADHAR
AGE  : 22
ADDR : VASNA.

$ sh29 detail.txt
Enter Even Number Of Arguments.

$ sh29 detail.txt temp1 temp2
Enter Even Number Of Arguments.