The value of a TixSelect widget is a list of the names of the button subwidgets that are currently selected. For example, in program 1-11, if the user has selected the apple button, then the value of the TixSelect widget will be apple. If the user has selected both the apple and the orange buttons, then the value will be the list "apple orange".
The TixSelect widget supports same set of options as the TixControl widget for you to access its value: the -value option stores the current value, which can be queried and modified using the cget and configure methods. You can also use the -variable option to specify a global variable to store the value of the TixSelect widget. The -command option specifies a TCL command to be called whenever the user changes the selection inside a TixSelect widget. This command is called with one argument: the new value of the TixSelect widget. There is also the -disablecallback option which you can use to control whether the command specified by the -command option should be called when the value of the TixSelect changes.