From -760739197640074814 X-Google-Language: ENGLISH,ASCII X-Google-Thread: f78e5,314ebdf2ff957e27 X-Google-Attributes: gidf78e5,public X-Google-ArrivalTime: 2003-04-15 17:01:38 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!kibo.news.demon.net!mutlu.news.demon.net!demon!mail2news.demon.co.uk!devnull From: kanze@gabi-soft.de (James Kanze) Newsgroups: comp.std.c++ Subject: Re: Why int main()? Date: Wed, 16 Apr 2003 00:01:37 +0000 (UTC) Organization: http://groups.google.com/ Lines: 53 Approved: fjh@cs.mu.oz.au (Fergus Henderson , moderator of comp.std.c++) Message-ID: References: <3E9821CE.8AC8B8C6@web.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: mail2news.demon.co.uk 1050451297 23630 10.0.0.1 (16 Apr 2003 00:01:37 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Wed, 16 Apr 2003 00:01:37 +0000 (UTC) X-Received: from mulga.cs.mu.oz.au ([128.250.1.22]) by news.demon.co.uk with esmtp (Exim 4.12) id 195aMq-00068q-00 for mail2news@news.news.demon.net; Wed, 16 Apr 2003 00:01:36 +0000 X-Received: from localhost (localhost [[UNIX: localhost]]) by mulga.cs.mu.OZ.AU id KAA11145; Wed, 16 Apr 2003 10:01:31 +1000 (EST) X-Authentication-Warning: mulga.cs.mu.OZ.AU: fjh set sender to devnull@stump.algebra.com using -f X-Path: comp-std-cpp-robomod!not-for-mail X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) X-Delivered-To: std-c++@ucar.edu X-Newsgroups: comp.std.c++ X-NNTP-Posting-Date: 15 Apr 2003 08:39:47 GMT X-Spamscanner: mailbox3.ucsd.edu (v1.2 Mar 17 2003 15:04:36, -0.4/5.0 2.43) X-MailScanner: PASSED (v1.2.7 25620 h3F8dlJC031191 mailbox3.ucsd.edu) X-Spam-Status: No, hits=-9.2 required=5.0 tests=EMAIL_ATTRIBUTION,NOSPAM_INC,QUOTED_EMAIL_TEXT,REFERENCES, SPAM_PHRASE_00_01 version=2.41 Xref: archiver1.google.com comp.std.c++:18764 terekhov@web.de (Alexander Terekhov) wrote in message news:<3E9821CE.8AC8B8C6@web.de>... > Francis Glassborow wrote: > > In article , Huw Ford > > writes > > >A lot of compilers will accept "void main()" so why must main > > >return an int? > > Because Standards are about portability. .... > In the next round, I'd probably try to make {thread::}main's return > type "application-chosen" -- other thread(s) (if any) could then join > and obtain whatever-return-value (if it's not void)... and adopt a > rather simple POSIX behavior of "passive exit" on last thread > termination. Oder? ;-) Interesting point of view. There are several interesting points, in fact: - Why int? That's what Unix and MS-DOS used, but it certainly isn't universal. The logical solution would have been an implementation defined type, main_t with only the return of the macros EXIT_SUCCESS and EXIT_FAILURE guaranteed by the standard. That would have broken a lot of existing programs, however. - Why not allow void? Either define falling off the end of a void main as equivalent to return EXIT_SUCCESS from a non-void main, or say that any return value is undefined (which is what actually happens in most implementations today). Or say that returning from a void main is illegal (undefined behavior) -- generally, when people write void main, it is because they don't return, either because the program consists of an endless loop, or because they always call exit. - And the business of threads introduces additional issues. Posix threads return a void*, for example, and not an int. Logically, I would expect a process to act sort of like a thread in the overall system, with a similar sort of return value. On the other hand, existing practice... -- James Kanze GABI Software mailto:kanze@gabi-soft.fr Conseils en informatique orient�e objet/ Beratung in objektorientierter Datenverarbeitung 11 rue de Rambouillet, 78460 Chevreuse, France, T�l. : +33 (0)1 30 23 45 16 --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.jamesd.demon.co.uk/csc/faq.html ]