anchor.diff:  :: FIXME (carbokuo) This script is migrated from bin/buck and bin/buck_common and still very incomplete.
   
   @echo off
  +
  +:: Check %JAVA_HOME%
  +if "%JAVA_HOME%"=="" (
  +  echo Please have JDK 1.7 or higher installed and set environment variable %%JAVA_HOME%%.
  +  exit /b
  +)
  +:: Check java
  +set JAVA=%JAVA_HOME%\bin\java.exe
  +if not exist "%JAVA%" (
  +  echo java.exe not found under "%JAVA_HOME%\bin". Please check your environment variable %%JAVA_HOME%%.
  +  exit /b
  +)
  +
   set ORIGINAL_WORKING_DIRECTORY=%cd%
   set PROJECT_ROOT=%cd%
   set BUCK_BIN_DIRECTORY=%~dp0
  
positive.code: set BUCKD_PORT_FILE=%PROJECT_ROOT%\buckd.port
  set BUCKD_RUNNING=0
  
  if exist %PROJECT_ROOT%\.buckversion (
    if not exist %PROJECT_ROOT%\.nobuckcheck (
      set /p BUCK_REQUIRED_VERSION=<%PROJECT_ROOT%\.buckversion
      rem TODO checkout the required version
    )
  
negative.code: :: The workaround is to write the output of the command into a temp file and read it.
  :: The name of the temp file contains a random number in order to avoid race condition.
  set BUCK_VERSION_TIMESTAMP_TEMPFILE=%TEMP%\BUCK_VERSION_TIMESTAMP_%RANDOM%.tmp
  if exist "%BUCK_GIT_DIRECTORY%" (
    for /f %%i in ('git --git-dir %BUCK_GIT_DIRECTORY% rev-parse HEAD') do set BUCK_CURRENT_VERSION=%%i
    git --git-dir %BUCK_GIT_DIRECTORY% log --pretty=format:%%ct -1 HEAD >%BUCK_VERSION_TIMESTAMP_TEMPFILE%
    set /p BUCK_VERSION_TIMESTAMP=<%BUCK_VERSION_TIMESTAMP_TEMPFILE%
  