@param buffer the evbuffer to be searched
@param what the string to be searched for
@param len the length of the search string
@param start NULL or a pointer to a valid evbuffer_ptr that
indicates where we should start searching.
@param end NULL or a pointer to a valid evbuffer_ptr that
indicates where we should stop searching.
@return a evbuffer_ptr whose 'pos' field has the offset of the
first occurrence of the string in the buffer after 'start'. The 'pos'
field of the result is -1 if the string was not found.
Search for a string within part of an evbuffer.
@param buffer the evbuffer to be searched @param what the string to be searched for @param len the length of the search string @param start NULL or a pointer to a valid evbuffer_ptr that indicates where we should start searching. @param end NULL or a pointer to a valid evbuffer_ptr that indicates where we should stop searching. @return a evbuffer_ptr whose 'pos' field has the offset of the first occurrence of the string in the buffer after 'start'. The 'pos' field of the result is -1 if the string was not found.