[Tclx] provides a binding to execl . : '''execl''' ?'''-argv0''' ''argv0''? ''prog'' ?''arglist''? Do an `execl`, replacing the current program (either Extended Tcl or an application with Extended Tcl embedded into it) with ''prog'' and passing the arguments in the list ''arglist''. If '''-argv0''' is specified, the zero'th argument will be ''argv0'' instead of the usual default (i.e., ''prog''). Note that if this command fails, it will not be save to use [Tk] from the current process any more. <> Command | TclX