Drawing Path

To get the full path, you append the DWGPREFIX system variable (which stores the path) to the DWGNAME system variable (which stores the file name).
Use code such as the following example to retrieve and assign the values of DWGNAME and DWGPREFIX to variables in AutoLISP : 

(setq DN (getvar "DWGNAME"))
(setq DP (getvar "DWGPREFIX"))

Use the AutoLISP function (strcat), to concatenate the results and assign them to a variable, for example : 

(setq TM (strcat DP DN))

In this example, the variable TM contains the full path including the file name.