Sets the tabs for the buffers. count specifies the size of tabs. The tab array will be deleted by the buffer, either when the buffer is deleted or when a new set of tabs is installed.
The array specifies the x-locations at which each tab occurs. Tabs beyond the last specified tab will be separated by a fixed amount tabWidth. If inUnits is TRUE if, then tabs are specified in canvas units; otherwsie, they are specified in space. (If tabs are specified in spaces, then the graphic tab positions will change with the font used for the tab.)