pack(p1) public

Packs the contents of arr into a binary sequence according to the directives in aTemplateString (see the table below) Directives ``A,’‘ ``a,’‘ and ``Z’‘ may be followed by a count, which gives the width of the resulting field. The remaining directives also may take a count, indicating the number of array elements to convert. If the count is an asterisk (``*’’), all remaining array elements will be converted. Any of the directives ``sSiIlL'' may be followed by an underscore (``_'') to use the underlying platform’s native size for the specified type; otherwise, they use a platform-independent size. Spaces are ignored in the template string. See also String#unpack.

   a = [ "a", "b", "c" ]
   n = [ 65, 66, 67 ]
   a.pack("A3A3A3")   #=> "a  b  c  "
   a.pack("a3a3a3")   #=> "a\000\000b\000\000c\000\000"
   n.pack("ccc")      #=> "ABC"

Directives for pack.

 Directive    Meaning
 ---------------------------------------------------------------
     @     |  Moves to absolute position
     A     |  ASCII string (space padded, count is width)
     a     |  ASCII string (null padded, count is width)
     B     |  Bit string (descending bit order)
     b     |  Bit string (ascending bit order)
     C     |  Unsigned char
     c     |  Char
     D, d  |  Double-precision float, native format
     E     |  Double-precision float, little-endian byte order
     e     |  Single-precision float, little-endian byte order
     F, f  |  Single-precision float, native format
     G     |  Double-precision float, network (big-endian) byte order
     g     |  Single-precision float, network (big-endian) byte order
     H     |  Hex string (high nibble first)
     h     |  Hex string (low nibble first)
     I     |  Unsigned integer
     i     |  Integer
     L     |  Unsigned long
     l     |  Long
     M     |  Quoted printable, MIME encoding (see RFC2045)
     m     |  Base64 encoded string
     N     |  Long, network (big-endian) byte order
     n     |  Short, network (big-endian) byte-order
     P     |  Pointer to a structure (fixed-length string)
     p     |  Pointer to a null-terminated string
     Q, q  |  64-bit number
     S     |  Unsigned short
     s     |  Short
     U     |  UTF-8
     u     |  UU-encoded string
     V     |  Long, little-endian byte order
     v     |  Short, little-endian byte order
     w     |  BER-compressed integer\fnm
     X     |  Back up a byte
     x     |  Null byte
     Z     |  Same as ``a'', except that null is added with *
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