Tcl/Tk 8.3 enhanced the capabilities of the canvas widget through the incorporation of the popular “dash” patch, as well as providing incremental improvements to other Tcl/Tk features.
Tcl 8.3 incorporated several key contributed patches, particularly for Tk. Jan Nijtmans's dash and image patches provided many handy features such as dashed lines on the canvas, improved image support, and more. Bringing these patches into the Tcl core not only provided new features usable in general Tcl scripts, but it allowed people to use several popular extensions and tools without the need for manually applying these patches and recompiling Tcl.
file channels command returns a list of open ...