HELPLIB.HLB  —  GOSUB
    Transfers control to a labeled subroutine in a command procedure
    without creating a new procedure level.

    Format

      GOSUB  label

1  –  Parameter

 label

    Specifies a label of 1 to 255 alphanumeric characters that
    appears as the first item on a command line. A label may not
    contain embedded blanks. When the GOSUB command is executed,
    control passes to the command following the specified label.

    The label can precede or follow the GOSUB statement in the
    current command procedure. When you use a label in a command
    procedure, it must be terminated with a colon (:).  If you use
    duplicate labels, control is always given to the label most
    recently read by DCL.

2  –  Example

  $!
  $! GOSUB.COM
  $!
  $ SHOW TIME
  $ GOSUB TEST1
  $ WRITE SYS$OUTPUT "success completion"
  $ EXIT
  $!
  $! TEST1 GOSUB definition
  $!
  $ TEST1:
  $     WRITE SYS$OUTPUT "This is GOSUB level 1."
  $     GOSUB TEST2
  $     RETURN %X1
  $!
  $! TEST2 GOSUB definition
  $!
  $ TEST2:
  $     WRITE SYS$OUTPUT "This is GOSUB level 2."
  $     GOSUB TEST3
  $     RETURN
  $!
  $! TEST3 GOSUB definition
  $!
  $ TEST3:
  $     WRITE SYS$OUTPUT "This is GOSUB level 3."
  $     RETURN

      This sample command procedure shows how to use the GOSUB
      command to transfer control to labeled subroutines. The GOSUB
      command transfers control to the subroutine labeled TEST1. The
      procedure executes the commands in subroutine TEST1, branching
      to the subroutine labeled TEST2. The procedure then executes
      the commands in subroutine TEST2, branching to the subroutine
      labeled TEST3. Each subroutine is terminated by the RETURN
      command. After TEST3 is executed, the RETURN command returns
      control back to the command line following each calling GOSUB
      statement. At this point, the procedure has been successfully
      executed.
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