5.2.35 Scroll a window

Procedure: scroll win

The scroll routine scrolls the window up one line. This involves moving the lines in the window data structure. As an optimization, if the scrolling region of the window is the entire screen, the physical screen may be scrolled at the same time.

Procedure: scrl win n

For positive n, the scrl and wscrl routines scroll the window up n lines (line i+n becomes i); otherwise scroll the window down n lines. This involves moving the lines in the window character image structure. The current cursor position is not changed.

For these functions to work, scrolling must be enabled via scrollok!.

It returns #f upon failure, and #t upon successful completion.