cmd
D:\>cat test.txt aD:\>echo add >> test.txt D:\>cat test.txt a add'>>'で追記 D:\>echo overwrite > test.txt D:\>cat test.txt overwrite '>'で上書き
D:\>cat test.txt aD:\>echo add >> test.txt D:\>cat test.txt a add'>>'で追記 D:\>echo overwrite > test.txt D:\>cat test.txt overwrite '>'で上書き