Doc: Update references and examples of old, unsupported OSes and uarc… · python/cpython@92f8786

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@@ -252,20 +252,25 @@ Binary Data

252252-----------

253253254254It is perfectly possible to send binary data over a socket. The major problem is

255-that not all machines use the same formats for binary data. For example, a

256-Motorola chip will represent a 16 bit integer with the value 1 as the two hex

257-bytes 00 01. Intel and DEC, however, are byte-reversed - that same 1 is 01 00.

255+that not all machines use the same formats for binary data. For example,

256+`network byte order <https://en.wikipedia.org/wiki/Endianness#Networking>`_

257+is big-endian, with the most significant byte first,

258+so a 16 bit integer with the value ``1`` would be the two hex bytes ``00 01``.

259+However, most common processors (x86/AMD64, ARM, RISC-V), are little-endian,

260+with the least significant byte first - that same ``1`` would be ``01 00``.

261+258262Socket libraries have calls for converting 16 and 32 bit integers - ``ntohl,

259263htonl, ntohs, htons`` where "n" means *network* and "h" means *host*, "s" means

260264*short* and "l" means *long*. Where network order is host order, these do

261265nothing, but where the machine is byte-reversed, these swap the bytes around

262266appropriately.

263267264-In these days of 32 bit machines, the ascii representation of binary data is

268+In these days of 64-bit machines, the ASCII representation of binary data is

265269frequently smaller than the binary representation. That's because a surprising

266-amount of the time, all those longs have the value 0, or maybe 1. The string "0"

267-would be two bytes, while binary is four. Of course, this doesn't fit well with

268-fixed-length messages. Decisions, decisions.

270+amount of the time, most integers have the value 0, or maybe 1.

271+The string ``"0"`` would be two bytes, while a full 64-bit integer would be 8.

272+Of course, this doesn't fit well with fixed-length messages.

273+Decisions, decisions.

269274270275271276Disconnecting