From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,dbaf05888e191cb6 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-01-17 10:08:14 PST Message-ID: <3E284591.3040706@cogeco.ca> From: "Warren W. Gay VE3WWG" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.0.1) Gecko/20020823 Netscape/7.0 X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Access to array slices? References: <5ad0dd8a.0301141717.2f1a9685@posting.google.com> <7teV9.60727$No.7357@sccrnsc04> <5ad0dd8a.0301151818.7931f6a3@posting.google.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 17 Jan 2003 13:04:01 -0500 NNTP-Posting-Host: 198.96.47.195 X-Complaints-To: abuse@sympatico.ca X-Trace: news20.bellglobal.com 1042826641 198.96.47.195 (Fri, 17 Jan 2003 13:04:01 EST) NNTP-Posting-Date: Fri, 17 Jan 2003 13:04:01 EST Organization: Bell Sympatico Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!nntp.cs.ubc.ca!torn!webster!nf1.bellglobal.com!nf2.bellglobal.com!news20.bellglobal.com.POSTED!not-for-mail Xref: archiver1.google.com comp.lang.ada:33152 Date: 2003-01-17T13:04:01-05:00 List-Id: Wojtek Narczynski wrote: ...snip... > When it comes to network byte order, this is a good thing: > > http://www.ibpaus.de/downloads/AdaStreamsInNetworkByteOrder_020326.tar.gz > > I think that GNAT using this is still compatible with RM, because byte > order for streams is not defined there. Correct? Depending upon the hosts used, this would appear to work fine. However, there is one warning I would like to suggest is worth looking into: The GNAT network byte ordering scheme only performs byte swapping based upon big/little endian machines. This raises two possible issues (one of which you can probably ignore): 1. The byte swapping method only works if machines at each end use the SAME FLOATING POINT REPRESENTATION. I believe most modern architectures do, but I know that the XDR routines (for RPC under UNIX), went out of their way to specify what the network floating point representation should be. This can be different than what is actually used on a particular local host (endian change or not). 2. Hopefully this no longer applies, but some of the old iron out there (PDP?) swapped words and bytes in conflicting order (words were big endian and bytes within the word were little endian (or maybe I got it backwards). If this is the case, the little/big endian conversions will simply not work. But you can probably ignore this issue today ;-) wwg. -- Warren W. Gay VE3WWG http://home.cogeco.ca/~ve3wwg