Analog of watch (GNU command-line tool) for Windows

watch.bat

@echo OFF

REM watch is a GNU command-line tool that runs the specified command repeatedly
REM and displays the output on stdout so you can watch it change over time.
REM By default, the command is run every two seconds, although this is adjustable with the -n secs argument.

if x%1==x (call :usage %0 %* && exit /b 1)

if x%1==x-n (
  if x%2==x (call :usage %0 %* && exit /b 1)

  for /f "tokens=2*" %%a in ("%*") do (
    rem ignore %%a==-n
    set INTERVAL=%%a
    set CMD=%%b
  )
) else (
  set INTERVAL=2
  set CMD=%*
)

:run

cls

@echo ON
%CMD%
@echo OFF
if errorlevel 1 ( goto :EOF )

timeout /t %INTERVAL% >nul 2>&1

goto :run


:usage
echo Usage: %1 [-n ^<seconds^>] ^<command with args^>
goto :EOF