ttyflags —
set device-specific flags for terminals
  
    | ttyflags | [ -v] [-a|
      tty ...] | 
ttyflags sets the device-specific flags for terminals
  using TIOCSFLAGS, based on the flags found on the
  terminal's line in /etc/ttys.
The options are as follows:
  - -a
- Set the flags for all terminals in /etc/ttys.
- -v
- Be verbose about what the terminals' flags will be set to.
The tty arguments are optional, but must not
    be specified if the -a flag is used. If specified,
    the tty arguments should be the base names of the
    ttys, as found in /etc/ttys.
The ttyflags utility appeared in NetBSD
  1.0.
The conditions on which to report an error are ill-defined.
  ttyflags tries to report all significant errors,
  perhaps going over-board at times.