link in php that catches the data from a form

what i need it to do is if someone types in sesilva that will send the message to sesilva.txt i need it to add a link at the buttom saying view msg here and it will link to whatever they typed .txt
like sesilva will send them to sesilva.txt i hope i said this so you can under stanmd what im saying

never worked with links befor in php

this is the best i can come up with

i get a error message

Wrong parameter count for link() in