IDString [FILENUM] STRING

    It terminates the program if the magic/signature at the current
    position of the file differs than the provided string.
    If the string doesn't match and it's 4 bytes long QuickBMS will
    automatically swap it and perform the comparison again and
    change the endianess if it matches. This solution makes most of
    the scripts written for an architecture (for example PC)
    virtually compatible with others (for example Xbox360).
    Pay attention to the FILENUM/VAR order different than other
    commands, that's a rule of the original BMS syntax.

    Arguments
      FILENUM   number of the file associated to the archive (0)
      STRING    string in C notation (cstring), it can also use
                wildcard bytes like "\x??" (they covers only the
                first 32 bytes of the string)

    Examples:
      IDString "PK\x03\x04"
      IDString " KAP"
      IDString MEMORY_FILE "hello"
      IDString 1 "magic_on_file_one"
      IDString "PK\x??\x??"