(I hope this is you guys & not Apple ...)
There are links from /usr/lib and /usr/include for tcl components but
not for tk ..
grendel:~/cf simon$ ls -l /usr/include/{tcl,tk}*
ls: /usr/include/tk*: No such file or directory
lrwxr-xr-x 1 root wheel 67 31 Mar 21:05 /usr/include/tcl.h -> /
System/Library/Frameworks/Tcl.framework/Versions/8.4/Headers/
tcl.h
lrwxr-xr-x 1 root wheel 72 31 Mar 21:05 /usr/include/tclDecls.h -> /
System/Library/Frameworks/Tcl.framework/Versions/8.4/Headers/
tclDecls.h
lrwxr-xr-x 1 root wheel 76 31 Mar 21:05 /usr/include/tclPlatDecls.h
-> /System/Library/Frameworks/Tcl.framework/Versions/8.4/
Headers/tclPlatDecls.h
grendel:~/cf simon$ ls -l /usr/lib/lib{tcl,tk}*
ls: /usr/lib/libtk*: No such file or directory
lrwxr-xr-x 1 root wheel 15 22 Jan 04:16 /usr/lib/libtcl.dylib ->
libtcl8.4.dylib
-r-xr-xr-x 1 root wheel 590292 16 Apr 15:49 /usr/lib/libtcl8.3.dylib
lrwxr-xr-x 1 root wheel 57 22 Jan 04:16 /usr/lib/libtcl8.4.dylib ->
/System/Library/Frameworks/Tcl.framework/Versions/8.4/Tcl
lrwxr-xr-x 1 root wheel 69 31 Mar 21:04 /usr/lib/libtclstub8.4.a ->
/System/Library/Frameworks/Tcl.framework/Versions/8.4/
libtclstub8.4.a
This machine was new at 10.3.7 (29 March). I installed Tcl/Tk Aqua
8.4.9 on 31 March. I've installed 10.3.8 & 10.3.9 since.
Logged In: YES
user_id=917025
I'm really sorry to have duplicated this; next time I'll be more careful about
using the 'back' facility, and take not of what Safari says about re-posting
form data.