http://www.purl.org/tcl/home/man/tcl8.4/TkCmd/bell.htm

 bell ?-displayof window?  

This command rings the bell on the display for window and returns an empty string. If the -displayof option is omitted, the display of the application's main window is used by default. The command uses the current bell-related settings for the display, which may be modified with programs such as xset. 
This command also resets the screen saver for the screen.  Some screen savers will ignore this, but others will reset so that the screen becomes visible again.  

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Anything special needed to use bell on Windows or MacOS?

[KBK] (2003-05-29) Just remember that [[bell]] is a Tk command, not a Tcl command, and there's no problem on Windows. (At least it works for me.)

[DKF] (2003-05-30) However, exactly how the "bell" sounds varies between platforms.  It's not always a simple beep, and shouldn't be rung frequently.  But then it shouldn't be rung frequently anyway...

Does bell require the Windows or MacOS user to have a Tk console open ?

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