[Iska]

По простому:

Код:

@echo off
setlocal enableextensions enabledelayedexpansion

set sSourceFile=0001.txt
set /a iCount = 3

call :GetTemporaryName

>nul copy nul "%TemporaryName%"
for /l %%i in (1, 1, %iCount%) do >nul copy /b "%TemporaryName%"+"%sSourceFile%" "%TemporaryName%"

>nul copy "%TemporaryName%" "%sSourceFile%"
del /f /q "%TemporaryName%"

endlocal
exit /b 0

rem ==========================================================================
rem Функция GetTemporaryName()
rem
rem Серый форум / CMD/BAT: генерация пути для временного файла или папки
rem (http://forum.script-coding.com/viewtopic.php?id=6259)
rem ==========================================================================
:GetTemporaryName
	setlocal enableextensions enabledelayedexpansion

:NextName
	set sTempName=%temp%\temp%random%.tmp

	if exist "%sTempName%" goto :NextName

	set sProcName=%~0

	endlocal & set %sProcName:~4%=%sTempName%
	exit /b 0
rem ==========================================================================