Radio Shack TRS-80 Model II Reference Manual page 15

MODEL II TRSDOS
OPEN
Statement
To specify a record length Of256, you can use either 256 ora. For example,
OPEN "0",1, "FILE", 256
and
OPEN "0", 1, "FILE". 0
are equivalent.
NEW
In addition to erasing the
BASIC
program in memory, this statement now clears the
screen.
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