COBOL Manual for TNS/E Programs (H06.08+, J06.03+)

proc-2
is the last procedure in the group.
test-site
BEFORE
specifies that the condition is to be tested before the perform range is executed. This is the
default.
AFTER
specifies that the condition is to be tested after the perform range is executed.
varying-phrase
specifies the outermost loop of the PERFORM statement control logic.
vary-1
is a numeric data item or an index. It is the iteration variable—the variable whose value
is changed each time the code in the outermost loop is executed.
base-1
is a numeric literal, an index-name, or the identifier of a numeric data item. It is the initial
value for vary-1.
step-1
is a numeric literal or the identifier of a numeric data item. It is the increment that is to be
added to vary-1 each time control returns from the end of the range of the PERFORM.
The value of step-1 must not be 0.
condition-1
is any conditional expression.
after-phrase
specifies additional inner loops of the PERFORM statement control logic. Up to six AFTER
phrases can be used in an out-of-line PERFORM statement. In COBOL, the AFTER phrase is not
permitted in the in-line PERFORM statement.
PERFORM 397