AT&T 6300 Programmer's Manual page 273

Syntax
(xl,y1)-(x2,y2)
array
Remarks
GET (Graphics)
Statement
Reads graphic images from the screen.
[GET] (xl,y1)-(x2,y2), array
are coordinates in either absolute or relative form defining a
screen area
is the name assigned to the array that will hold the image
The GET statement should be used in
conjunction with the PUT statement. GET
transfers the screen image bounded by the
rectangle described by the specified points
into the array. The rectangle is defined the
same way as the rectangle drawn by the LINE
statement using the ",B" option.
PUT transfers graphics images to the screen.
GET and PUT permit animation and high-
speed object motion.
The array must be numeric, but may be any
precision.
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