Exporting JTAG functions from DLL to Tcl

I'm trying to export the functions read, write, open and close from the "jtag_atlantic.dll" file into a tcl script. I've tried using the load command but it hasn't worked for me yet. Basically the idea is to map theses functions on to tcl commands, thereby creating new commands for these functions in tcl. Can anyone help me in this regard?