=over

=item HANDLE->format_lines_per_page(EXPR)

=item $FORMAT_LINES_PER_PAGE

=item $=
X<$=> X<$FORMAT_LINES_PER_PAGE>

The current page length (printable lines) of the currently selected
output channel.  Default is 60.  
Used with formats.
(Mnemonic: = has horizontal lines.)

=back