Xref: utzoo comp.arch:3306 comp.windows.x:2390
Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!ll-xn!mit-eddie!uw-beaver!cornell!batcomputer!pyramid!prls!mips!hansen
From: hansen@mips.COM (Craig Hansen)
Newsgroups: comp.arch,comp.windows.x
Subject: X data communications conventions (was Re: RISC data alignment)
Message-ID: <1464@mips.mips.COM>
Date: 2 Feb 88 21:11:25 GMT
References: <2635@calmasd.GE.COM> <6280@ccv.bbn.COM> <3120@phri.UUCP> <21152@clyde.ATT.COM>
Followup-To: comp.windows.x
Lines: 22
Keywords: alignment 68000 8086
Summary: x data communications conventions

In article <21152@clyde.ATT.COM>, gwu@clyde.ATT.COM (George Wu) writes:
>      Okay, so what formats are used? I  know X-Windows has some such convention
> to transmit binary data across the network, ie. a client and a server on
> different machines. What format do they use?

In X, the server gets stuck having to take data in either byte order,
possibly swapping the incoming data, except for bitmaps which are
always (mumble)-endian.  In my last reading of the X protocol, I
couldn't find a good justification for bitmaps being different.

> (Hopefully, Roy will expand
> upon hton() and XDR. I think ASCII is self-explanatory.)

hton() basically converts to big-endian. XDR is a system of passing
data through procedures to translate it into and out of a "standard"
external data representation, whose resemblance to Sun's internal
data representation is purely coincidental... ;->

-- 
Craig Hansen
Manager, Architecture Development
MIPS Computer Systems, Inc.
...{ames,decwrl,prls}!mips!hansen or hansen@mips.com   408-991-0234