how to restart pointer 'line'

[heziro]

hello

I"m read a text file in VHDL and i want that in the end of the file it will start again.
I tried to save the pointer (line) in other pointer and after the file end to restart the pointer by the other pointer

like that:

b (other pointer) := a (line pointer)
.
.
read the text
.
.
a:= b

unfortunately it isn't work.
i think that it because (like in c++) pointer b is point on pointer a
and when pointer a is change, pointer b change too!

does someone know how to restart the pointer?
how i do that pointer b will point on the data of pointer a and not on him?

thanks
hezi