+.PP
+X/Open does not define any error conditions.
+.PP
+In this implementation, those functions that have a window pointer
+will return an error if the window pointer is null.
+.RS
+.TP 5
+.B wclrtoeol
+returns an error
+if the cursor position is about to wrap.
+.TP 5
+.B wsetscrreg
+returns an error if the scrolling region limits extend outside the window.
+.RE
+.PP
+X/Open does not define any error conditions.
+This implementation returns an error
+if the window pointer is null.