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Doc: Update references and examples of old, unsupported OSes and uarches (GH-92791) (GH-93638)

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(cherry picked from commit a5ba0f4ebc)

Co-authored-by: CAM Gerlach <CAM.Gerlach@Gerlach.CAM>
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Miss Islington (bot) 2022-06-09 07:15:33 -07:00 • committed by GitHub
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19
Doc/howto/sockets.rst
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@ -252,20 +252,25 @@ Binary Data
-----------
It is perfectly possible to send binary data over a socket. The major problem is
that not all machines use the same formats for binary data. For example, a
Motorola chip will represent a 16 bit integer with the value 1 as the two hex
bytes 00 01. Intel and DEC, however, are byte-reversed - that same 1 is 01 00.
that not all machines use the same formats for binary data. For example,
`network byte order <https://en.wikipedia.org/wiki/Endianness#Networking>`_
is big-endian, with the most significant byte first,
so a 16 bit integer with the value ``1`` would be the two hex bytes ``00 01``.
However, most common processors (x86/AMD64, ARM, RISC-V), are little-endian,
with the least significant byte first - that same ``1`` would be ``01 00``.
Socket libraries have calls for converting 16 and 32 bit integers - ``ntohl,
htonl, ntohs, htons`` where "n" means *network* and "h" means *host*, "s" means
*short* and "l" means *long*. Where network order is host order, these do
nothing, but where the machine is byte-reversed, these swap the bytes around
appropriately.
In these days of 32 bit machines, the ascii representation of binary data is
In these days of 64-bit machines, the ASCII representation of binary data is
frequently smaller than the binary representation. That's because a surprising
amount of the time, all those longs have the value 0, or maybe 1. The string "0"
would be two bytes, while binary is four. Of course, this doesn't fit well with
fixed-length messages. Decisions, decisions.
amount of the time, most integers have the value 0, or maybe 1.
The string ``"0"`` would be two bytes, while a full 64-bit integer would be 8.
Of course, this doesn't fit well with fixed-length messages.
Decisions, decisions.
Disconnecting