EFI Shell commands -- FOR(在一個項目集合中，去行一個或多個指令對於每個項目)

Executes one or more commands for each item in a set of items.

FOR %indexvar IN set
    command [arguments]
    [command [arguments]]
     ...
ENDFOR


FOR %indexvar RUN (start end[ step])
    command [arguments]
    [command [arguments]]
    ...
ENDFOR


    %indexvar           - Variable name used to index a set
    set                  - Set to be searched
    command [arguments]  - Command to be executed with optional arguments

Note:
    1. The FOR command is only available in batch script files.
    2. FOR shall be matched with ENDFOR.
    3. start and end can be any integer.  Up to 6 digits allowed.
    4. step can be any integer but zero.  Up to 6 digits allowed.
    5. step is optional, if step is not specified, step will be automatically
       determined as below:
         if start <= end, then step = 1
         if start > end,  then step = -1

Examples:
    #
    #  Sample for loop type contents of all *.txt files
    #
    for %a in *.txt
       type %a
       echo ===== %a done =====
    endfor

    #
    #  To repeat operations, supporting multiple loop:
    #
        for %a in 1 2 3 4 5 6 7 8 9
          for %b in a b c d e f g h i j k l m n o p q r s t u v w x y z
            alias %a a%a
            alias %b %b%a
          endfor
        endfor

        for %a run (1 3)
          echo %a
        endfor
Output:
1
2
3

        for %a run (3 1)
          echo %a
        endfor
Output:
3
2
1