From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [9fans] GNU Make From: John Murdie To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu> In-Reply-To: References: Content-Type: text/plain Message-Id: <1086167278.1328.5.camel@pc118> Mime-Version: 1.0 Date: Wed, 2 Jun 2004 10:07:58 +0100 Content-Transfer-Encoding: 7bit Cc: john@cs.york.ac.uk Topicbox-Message-UUID: 8ff3e8b8-eacd-11e9-9e20-41e7f4b1d025 On Wed, 2004-06-02 at 08:36, Charles Forsyth wrote: > >>all Plan 9 software to use a library of error messages that also > >>includes a numeric code? > > Numeric codes are a bad idea, that plan 9 was well rid of from unix. > they do not scale well in a distributed system with distributed development. > > even the internet protocols that use them tend to degenerate into `good, bad, ugly' > based on the first digit (0, 4, 5 say). > > it's just one reason that NFS had terrible trouble across systems with > different errno values. precise diagnostics ended up being mapped into EIO, > which wasn't always the right answer, just because there was no portable > way to convert an arbitrary code from one system to an arbitrary code in another. > n*m indeed. of course, you could have MegaErrnoInc act as a global > registry of mappings, as Sun tried with Sun RPC, but for this application it doesn't > work well. > > some uniformity in the error strings would be desirable, > but numeric codes should not be used. I, too, dislike numeric error codes, but how do you think multiple natural languages should be accommodated? I've no experience of this with Plan 9. Does it cope well? John A. Murdie Department of Computer Science University of York