overlay string, it pushes on the iterator stack the state variables
describing its iteration of buffer text, then reinitializes the iterator
object for processing the property or overlay. The it->sp ("stack
- pointer") member, if it is greater than zero, means the iterators stack was
- pushed at least once. You can therefore condition your breakpoints on the
- value of it->sp being positive or being of a certain positive value, to
+ pointer") member, if it is greater than zero, means the iterator's stack
+ was pushed at least once. You can therefore condition your breakpoints on
+ the value of it->sp being positive or being of a certain positive value, to
debug display problems that happen only with display properties or
overlays.