Search tclConfig.sh and tkConfig.sh...................
Valid [tclConfig.sh, tkConfig.sh] are found in [["/usr/lib", "/usr/lib"]]
Use [tclConfig.sh, tkConfig.sh] == ["/usr/lib/tclConfig.sh", "/usr/lib/tkConfig.sh"]
Use X11 libraries (or use TK_XINCLUDES/TK_XLIBSW information on tkConfig.sh).
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**
** NATIVETHREAD SUPPORT MODE WARNING:
**
**   Ruby is compiled with --enable-pthread, but your Tcl/Tk library
**   seems to be compiled without nativethread support. Although you can
**   create the tcltklib library, this combination may cause errors (e.g.
**   hangs or segmentation faults). If you have no reason to keep the
**   current nativethread support status, we recommend you reconfigure and
**   recompile the libraries so that both or neither support nativethreads.
**
**   If you want change the status of nativethread support, please recompile
**   Ruby without "--enable-pthread" configure option (If you use Ruby 1.9.x
**   or later, you cannot remove this option, because it requires native-
**   thread support.) or recompile Tcl/Tk with "--enable-threads" configure
**   option (if your Tcl/Tk is later than or equal to Tcl/Tk 8.1).
**
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Find Tcl/Tk libraries. Make tcltklib.so which is required by Ruby/Tk.
configuring tk/tkutil