From -1227347609793249575 X-Google-Thread: f78e5,d9988170196edb06 X-Google-Attributes: gidf78e5,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news3.google.com!news.glorb.com!news.alt.net!comp-std-cpp-robomod!not-for-mail From: "Roger Orr" Newsgroups: comp.std.c++ Subject: Re: Other headers #included via iostream Date: 19 Jul 2005 23:10:02 GMT Organization: "Altopia Corp. - Usenet Access - www.altopia.com" Lines: 35 Approved: Fergus Henderson , moderator of comp.std.c++ Message-ID: References: Return-Path: X-Authentication-Warning: mulga.cs.mu.OZ.AU: fjh set sender to devnull@stump.algebra.com using -f X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) Delivered-To: std-c++@ucar.edu X-Trace: news.demon.co.uk 1121814148 1470 80.177.1.3 (19 Jul 2005 23:02:28 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Tue, 19 Jul 2005 23:02:28 +0000 (UTC) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.3790.326 X-Priority: 3 X-Newsreader: Microsoft Outlook Express 6.00.3790.326 X-MSMail-Priority: Normal X-Greylisting: NO DELAY (Relay+Sender autoqualified); processed by UCSD_GL-v1.3 on mailbox8.ucsd.edu; Tue, 19 July 2005 16:06:47 -0700 (PDT) X-Spamscanner: mailbox8.ucsd.edu (v1.6 Apr 6 2005 07:48:50, -1.6/5.0 3.0.0) X-MailScanner: PASSED (v1.2.8 65726 j6JN2VkD069079 mailbox8.ucsd.edu) X-Virus-Scanned: amavisd-new at ucar.edu X-Virus-Scanned: amavisd-new at cs.mu.OZ.AU X-Virus-Scanned: amavisd-new at cs.mu.OZ.AU Xref: g2news1.google.com comp.std.c++:1399 wrote in message news:si3qd1l5ls9fmjbiatgmrcgetbcp6qbss6@4ax.com... > Hi, > > As most of you probably already know, depending on which > implementation of C++ you have, #include may cause various > other headers to be #included too. (I've observed cstring, cstdio, > cmath and I think cstdlib in g++) > > Are there any that the standard requires to be "dragged in" like this > regardless of implementation? No - in fact all that is required is the declaration of cin, cout, cerr and clog and the wide character equivalents. Why do you want to know? In general do not make _any_ assumptions about the 'other' header files which may be included by a standard header - explicitly include what you need. I know this is easier said than done, but it improves portability (across platforms, or even across versions of compiler) if you try to do this. Regards, Roger Orr -- MVP in C++ at www.brainbench.com --- [ 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 ]