tclVarFun
(Package: tcltk2) :
Manipulate R variables and functions from tcl and back
These functions are intended to provide a better "duality" between the name of variables in both R and tcl, including for function calls. It is possible to define a variable with the same name in R and tcl (the content is identical, but copied and coerced in the two respective environments). It is also possible to get the value of a tcl variable from R, and to call a R function from within tcl. These functionnalities are provided in the tcltk package, but Tcl variable usually have different internal names as R equivalents.
tclTask
(Package: tcltk2) :
Schedule and manage delayed tasks
Tcl allows fo scheduling execution of code on the next event loop or after a given time (after Tcl command). tclTaskXxx() functions use it to schedule execution of R code with much control from within R (central management of scheduled tasks, possibility to define redoable tasks, use of S3 objects to keep track of tasks information. The tclAfterXxx() functions are low-level access to the Tcl after command.
tk2ico
(Package: tcltk2) :
Manipulate icons under Windows
Create, load and work with Windows icons. Change icons fo Windows, use icons in the taskbar under Windows 9X/2000/XP, ... These function are only useful for Windows, but they silently return NULL on other platforms for writing compatible code (Windows icons instructions can be simply ignored).
tk2reg
(Package: tcltk2) :
Manipulate the registry under Windows
These functions access the Windows registry in a secure way (most errors are handled gracefully), and ensures correct conversion back and forth for atomic strings ('sz' and 'expand_') and numbers ('dword' and 'dword_big_endian'), and for vectors of strings ('multi_sz').
tk2dde
(Package: tcltk2) :
Use DDE (Dynamic Data Exchange) under Windows
DDE is the first Microsoft's attempt to make an inter-application mechanism. It is now superseeded by (D)Com, but it is still available. Being simpler than Com, DDE is interesting for simple tasks. Applications like Word, Excel, Windows Explorer, Internet Explorer, etc... provide services one can access through DDE (see examples).
providing 
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