Batch to make Atom portable

Atom.bat

@echo off
:: Get current drive's letter.
set a=%~dp0
echo Base path: %a%

:: Filesystem checking.
if not exist "%a%\Atom" (
	echo [ERROR]Atom folder not found.
	goto error
)

if not exist "%a%\Atom\atom.exe" (
	echo [ERROR]Atom executable not found.
	goto error
)

:: Environment vars setting
set ATOM_HOME=%a%\Atom\data
set USERPROFILE=%ATOM_HOME%
set APPDATA=%USERPROFILE%\AppData

echo ATOM_HOME: %ATOM_HOME%
echo USERPROFILE: %USERPROFILE%
echo APPDATA: %APPDATA%

if not exist "%ATOM_HOME%" mkdir "%ATOM_HOME%"
if not exist "%USERPROFILE%\AppData" mkdir "%USERPROFILE%\AppData"
if not exist "%USERPROFILE%\AppData\Roaming" mkdir "%USERPROFILE%\AppData\Roaming"
if not exist "%USERPROFILE%\Desktop" mkdir "%USERPROFILE%\Desktop"

:: Go to atom's folder and launch it.
:launch
cd Atom
start "" atom.exe
goto exit

:error
echo [ERROR]Atom folder MUST be in %a%, named Atom and atom's executable MUST be named atom.exe
set /p m=Press any key to leave...
goto exit

:exit