@echo off
rem -- dummy scenario always returns OK
setlocal enabledelayedexpansion

rem put argument to array stored in argVec
set argCount=0
for %%x in (%*) do (
   set /A argCount+=1
   set "argVec[!argCount!]=%%~x"
)

echo Number of processed arguments: %argCount%

rem foreach argVec (skip first) to copy files and add new file extension
for /L %%i in (2,1,%argCount%) do copy /y "!argVec[%%i]!" "!argVec[%%i]!!argVec[1]!"


exit 0