How do I find the number of lines of text in a field

[Steve Austin]

I know that

FieldType *field;

field->lines

is a pointer to a list of LineInfoTypes, but how do I dertermine how many
items are in this list?
Is the list terminated with a NULL record or something?  Or do I have to use
the field's rectangle and the
field's text to decide how many lines the field holds?

Thanks very much

Steve Austin