Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Message-ID: <007e01c4e609$0c577990$0200a8c0@mindcooler> From: =?iso-8859-1?Q?Mikael_=C5sberg?= To: "Cygwin List" Subject: Re: Where did the output go and question regarding return values of getopt_long() Date: Sun, 19 Dec 2004 21:26:40 +0100 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit "Larry Hall" wrote > At 10:14 AM 12/19/2004, you wrote: >>Hello, consider this c++-function: >> >>void >>handle_command_line(int argc, >> char* const argv[], >> bool& verbose, >> vector& numbers) >>{ >> const int id_numbers = 4711; >> const int id_verbose = 4712; >> const int id_help = 4713; >> >> const option long_options[] = >> { >> {"numbers", 1, NULL, id_numbers}, >> {"verbose", 0, NULL, id_verbose}, >> {"help", 0, NULL, id_help}, >> {NULL, 0, NULL, 0} >> }; >> >> const char* const short_options = ""; >> >> int c = 0; >> >> while((c = getopt_long( >> argc, >> argv, >> short_options, >> long_options, >> NULL)) != -1) >> { >> switch(c) >> { >> cout << "c = " << c << endl; /* Never shown on screen... */ >> >> case id_numbers: >> { >> cout << "Calling extract_numbers() with " << optarg << endl; >> >> extract_numbers(optarg, numbers); >> >> break; >> } >> case id_verbose: >> { >> cout << "Setting verbose = true" << endl; >> >> verbose = true; >> >> break; >> } >> case id_help: >> { >> cout << "TODO: Add short description regarding usage here." << >> endl; >> >> exit(EXIT_SUCCESS); >> } >> /* c seems to equal '?' for missing parameter as well... */ >> case ':': >> { >> cerr << "Missing parameter." << endl; >> >> break; >> } >> /* Only triggers for unknown options beginning with -- */ >> case '?': >> { >> cerr << "Ignoring unknown option." << endl; >> >> break; >> } >> default: >> { >> /* Throw exception? */ >> cerr << "Should not be reached." << endl; >> } >> } >> } >>} >> >>My first question is about the >>cout << "c = " << c << endl; >>inside the switch. I never see this output, why? I tried writing the >>output to a file as well but that file was empty when the program >>finished. All other "output-statements" are displayed just fine in this >>function (and the rest of the program). > > Did you look at the warning you get from the line in question? > > warning: unreachable code at beginning of switch statement > > Lol, of course! It's not reachable...I should've seen that. Anyway, I always compile with -Wall -W -ansi -pedantic and my homebrewn gcc-3.4.3 didn't yield any warnings at all. Thanks for the help, Larry! One question answered. I'm still wondering about the return values of getopt_long(), though, and I will try the same code on Fedora as soon as I get it setup properly on my laptop. / Mikael > > -- > Larry Hall http://www.rfk.com > RFK Partners, Inc. (508) 893-9779 - RFK Office > 838 Washington Street (508) 893-9889 - FAX > Holliston, MA 01746 > > -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/