value of nil means search to the end of the accessible portion of
the buffer.
The optional third argument NOERROR indicates how errors are handled
- when the search fails. If it is nil or omitted, emit an error; if
+ when the search fails: if it is nil or omitted, emit an error; if
it is t, simply return nil and do nothing; if it is neither nil nor
t, move to the limit of search and return nil.
The optional fourth argument COUNT is a number that indicates the