%RANDOM% は 0 から 32767 (2^15 - 1) まで。 %ERRORLEVEL% は -2147483648 (2^31) から 2147483647 (2^31 - 1) まで。 (Windows 7 32bit)

random.cmd

@echo off
rem -*- coding: shift_jis-dos -*-

call :MAIN
exit /b

:MAIN
setlocal enabledelayedexpansion
for /l %%i in (-1, 1, 10) do (
    call :RANDOM_N %%i
    set n=!ERRORLEVEL!
    if !n! neq -1 (
        set z=
        for /l %%j in (1, 1, %%i) do (
            set z=0!z!
        )
        set n=!z!!n!
        set n=!n:~-%%i!
    )
    echo %%i : !n!
)
exit /b
endlocal

:RANDOM_N
setlocal enabledelayedexpansion
if %1 leq 0 (
    exit /b -1
) else if %1 geq 10 (
    exit /b -1
)
call :RANDOM_4
set n=000%ERRORLEVEL%
for /l %%i in (4, 4, %1) do (
    call :RANDOM_4
    set n=000!ERRORLEVEL!!n:~-%%i!
)
set n=!n:~%1!
exit /b %n%
endlocal

:RANDOM_4
setlocal
set /a n=(%RANDOM% * 10000) / 32768
exit /b %n%
endlocal