input type and filename value

i have code that prints out a html form that will
send a file to a cgi script but id like
to do an error check and when someone leaves
out one of the options they will be sent
back to the same script and whatever
they filled in before will be filled in again

i tried this with:

 It was $textfile<br>     <input type="file" name="fileName" value="$textfile"><BR>

now with all the other fields (which we just text boxes and drop down menus) this method of assigning value to be some value (ie value="$previous_entry1") worked every time but not for when i try
to have an entry for a file.....

in the code

 It was $textfile<br>     <input type="file" name="fileName" value="$textfile"><BR>

it prints out what $textfile was but it will not put the value of $textfile in the textbox.....

ie it says
it was text.txt (and then it prints and empty text box - with no "text.txt"

how do i get it to put the value into the textbox?