Box records in gdsii files

[jmailguard-1@yahoo.com]

In gdsii files, what are box records used for? How should they be
interpreted by a gdsii reader? Are they generated by many cad
programs?

I've seen some cadence documentation that says that they should have 5
XY coordinates (similar to a boundary) and other cadence documentation
that says that they are defined by a center coordinate and width and
height. Which is correct?

 

[jmailguard-1@yahoo.com]

Thank you, but that didn't really answer my question. There seems to
be no readily available information about several things related to box
records:

1-How are boundary and box records different? Why would a cad program
write out a box record instead of a boundary record?
2-What is the meaning of BOXTYPE?
3-There is conflicting cadence documentation on the XY data. One
reference says the XY should have 5 points (I assume the points define
the perimeter of the box) another reference says that the XY data
should contain the center point and height/width information.
4-Are box records generally accepted by cad programs / foundaries? The
mosis website says that box records are read but ignored.