tk4.2 User Commands - tkvars
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 ini-
tialization file that is normally processed
whenever a Tk application starts up, plus
other files containing procedures that imple-
ment default behaviors for widgets. The ini-
tial 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 appropriate direc-
tory, then Tk checks several other direc-
tories based on a compiled-in default loca-
tion, the location of the Tcl library direc-
tory, the location of the binary containing
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 current
patch level for Tk. The patch level is
incremented for each new release or patch,
and it uniquely identifies an official ver-
sion of Tk.
tkPriv This variable is an array containing several
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 number increases
in any Tk release that includes changes that
are not backward compatible (i.e. whenever
existing Tk applications and scripts may have
to change to work with the new release). The
minor version number increases with each new
release of Tk, except that it resets to zero
whenever the major version number changes.
KEYWORDS
variables, version