Dave wrote:

My first thought was to use regex_search and pass it two stream iterators, one pointing to the beginning of the file and one representing the end of the file. Alas, this won't work since regex_search requires bidirectional iterators, which stream iterators are not.

You might consider using a file_iterator from Spirit. It is a random-access iterator for files, which sounds like exactly what you need. Check it out at http://www.boost.org/libs/spirit/doc/file_iterator.html. -- Todd