grep is indeed the answer to your question if you can be sure that the whole of the 'a' ... '/a' phrase is on the same line.
in reply to How to extract an email address from a mailto URL?
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James