Module Core_kernel.Binary_packing

The functions ending with _big_endian or _little_endian are faster than the ones with an explicit byte_order argument:

                                Name | Run time | S. dev. | Warnings
  ---------------------------------- | -------- | ------- | --------
        pack_signed_16_little_endian |     4 ns |    0 ns |
      unpack_signed_16_little_endian |     5 ns |    0 ns |
                  pack_signed_32_int |    12 ns |    0 ns |
                unpack_signed_32_int |    12 ns |    0 ns |
    pack_signed_32_int_little_endian |     4 ns |    0 ns |
  unpack_signed_32_int_little_endian |     5 ns |    0 ns |        M
                  pack_signed_64_int |    21 ns |    0 ns |        M
                unpack_signed_64_int |    21 ns |    0 ns |        M
        pack_signed_64_little_endian |     8 ns |    0 ns |
      unpack_signed_64_little_endian |     9 ns |    0 ns |        M

As with integers, floats can be be packed big-endian or little-endian, depending on the order in which the bytes of the float are layed out. There is nothing interesting going on computationally from a floating-point perspective, just laying out eight bytes in one order or the other.

Decode the fixed-length tail-padded string having length len from buf starting at pos. Return a string containing only the non-padding characters. The default padding is '\x00'.

Encode and pack the given string as a tail padded fixed length string having length len. Place it in buf starting at position pos. If the length of the string is less then len pad it with the padding characters until its length is equal to len. If the string is longer than len raise Invalid_argument. The default padding is '\x00'.