NAME
       tkvars - Variables used or set by Tk


DESCRIPTION
       The  following  Tcl variables are either set or used by Tk
       at various times in its execution:

       tk_library     This variable holds the  file  name  for  a
                      directory   containing  a  library  of  Tcl
                      scripts  related  to  Tk.   These   scripts
                      include an initialization file that is nor-
                      mally processed whenever a  Tk  application
                      starts up, plus other files containing pro-
                      cedures that  implement  default  behaviors
                      for   widgets.    The   initial   value  of
                      tcl_library is set when Tk is added  to  an
                      interpreter;   this  is  done  by searching
                      several different directories until one  is
                      found   that  contains  an  appropriate  Tk
                      startup script.  If the TK_LIBRARY environ-
                      ment variable exists, then the directory it
                      names  is  checked  first.   If  TK_LIBRARY
                      isn't  set or doesn't refer to an appropri-
                      ate directory, then Tk checks several other
                      directories  based on a compiled-in default
                      location, the location of the  Tcl  library
                      directory,  the location of the binary con-
                      taining the application,  and  the  current
                      working  directory.   The  variable  can be
                      modified by an application to switch  to  a
                      different library.

       tk_patchLevel  Contains  a decimal integer giving the cur-
                      rent patch level for Tk.  The  patch  level
                      is  incremented  for  each  new  release or
                      patch, and it uniquely identifies an  offi-
                      cial version of Tk.

       tkPriv         This  variable  is an array containing sev-
                      eral pieces of information that are private
                      to  Tk.  The elements of tkPriv are used by
                      Tk library procedures and default bindings.
                      They  should  not  be  accessed by any code
                      outside Tk.

       tk_strictMotif This variable is set to  zero  by  default.
                      If  an  application sets it to one, then Tk
                      attempts to adhere as closely  as  possible
                      to   Motif  look-and-feel  standards.   For
                      example, active elements  such  as  buttons
                      and scrollbar sliders will not change color
                      when the pointer passes over them.
       tk_version     Tk sets this variable  in  the  interpreter
                      for  each  application.  The variable holds
                      the  current  version  number  of  the   Tk
                      library in the form major.minor.  Major and
                      minor are integers.  The major version num-
                      ber   increases  in  any  Tk  release  that
                      includes changes that are not backward com-
                      patible (i.e. whenever existing Tk applica-
                      tions and scripts may  have  to  change  to
                      work with the new release).  The minor ver-
                      sion number increases with each new release
                      of  Tk, except that it resets to zero when-
                      ever the major version number changes.


KEYWORDS
       variables, version
