nul && echo exist Determine the directory /boot /exists, if it exists, then the output exist (this method is invalid for an empty directory) ls /boot> nul && echo exist!
Echo not exist Determine whether there is a file name of the current directory (working directory) to boot the beginning of the file or directory, if it exists, then the output exist, otherwise the output not exist ls (hd0,0) /boot /> nul && echo exist! Echo not exist Judgment directory (hd0,0) /boot /exists, if it exists, then the output exist, otherwise the output not exist [Note: If no file folder, for the ls command is concerned that the folder does not exist. ============================== Before use all menu items: default 0 The first menu item is selected by default (if the user does not manually select words) default saved The default selection is set to the last savedefault saved menu item (savedefault executed in menu item, the default saved to /default file) default /FILE The default selection is set to the last savedefault save menu item (savedefault executed in menu item, the default saved to /FILE file) e.g. Default default is often used where default is a 2048-byte file. [Note: /default file or /FILE file must be 2048 bytes in size] ============================== Used in the menu items: savedefault The current menu item as the default menu is saved to /default or the default command to specify the /FILE in. Savedefault --wait=5 The current menu item to save as the default menu /default or the default command to specify the /FILE, the first five seconds to save the user a hint: About to write the entry number x to file Press Y to allow or N to deny. If the user does not press the Y button, the default within five seconds does not save menu item.
============================== Before use all menu items: timeout 10 Menu list appears after 10 seconds, if the user does not manually select the default menu item to perform. ============================== title menu title Specifies the text of the menu item title title menu title n menu prompts the first line n menu prompts the second line n. The title text and text prompts to specify the menu item [Note: If the menu item does not start sensitive command, the menu key to select the vertical direction is not only key to select the right direction. Setmenu --box l=0 removes numbers and highlighted space at left of menu beep 2018-06 and later - play tones [Frequency Hz] [Duration ms] beep [--start --mid --end] [--play=N] [--nowait] FREQUENCY DURATION FREQUENCY DURATION. FREQUENCY: Hz. DURATION: ms. Max: 126 notes per command.