EFI Shell commands -- HELP(顯示指令說明)

Displays the EFI Shell command list or verbose help for specific commands.

HELP [cmd | pattern]

    cmd      - Shell command name
    pattern  - Wildmatch pattern

Note:
    1. 'cmd -?' also displays the verbose help of cmd, the same as 'help cmd'.
    2. If the specified command has no verbose help, its line help will be
       displayed instead.

Examples:
* To display the EFI Shell command list and break after one screen:
  Shell> help -b
  ?          - Displays the EFI Shell command list or verbose command help
  alias         - Displays, creates, or deletes aliases in the EFI Shell
  attrib     - Displays or changes the attributes of files or directories
  cd         - Displays or changes the current directory
  cls           - Clears the standard output with an optional background color
  connect    - Connects one or more EFI drivers to a device
  copy       - Copies one or more files or directories to another location
  ...

* To display help information for the ls shell command:
  Shell> help ls
  Shell> ? ls
  Shell> ls -?

* To display the list of commands starting with the character 'p'
  Shell> help p*
  pause      - Prints a message and waits for keyboard input
  pci        - Displays PCI device list or PCI function configuration space