bellctrl —
opm bell emulation preference utility
  
    | bellctrl | [ -b] [b
      on/off] [b
      [volume [pitch
      [duration]]]] [v
      default] [-vvoicefile] | 
bellctrl is used to set various preference options of
  the opm bell.
The options are as follows:
  - -b
- The b option controls bell volume, pitch and duration. This option accepts
      up to three numerical parameters, a preceding dash(-), or an 'on/off'
      flag. If no parameters are given, or the 'on' flag is used, the system
      defaults will be used. If the dash or 'off' are given, the bell will be
      turned off. If only one numerical parameter is given, the bell volume will
      be set to that value, as a percentage of its maximum. Likewise, the second
      numerical parameter specifies the bell pitch, in hertz, and the third
      numerical parameter specifies the duration in milliseconds.
- v default
- The default argument cause the voice parameter to be
      reset to the system default.
- -vvoicefile
- The -voption sets the voice parameter to given
      voice parameter file ( voicefile).
Abellctrl utility first appeared in
  NetBSD 1.3.