C++Talk.NET C++ language newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  calling GNUPLOT from a c++ program          C++Talk.NET Forum Index -> C++ language (comp.lang.c++) View previous topic :: View next topic   Author Message Joseph Suprenant Guest Posted: Sun Oct 26, 2003 3:36 pm    Post subject: calling GNUPLOT from a c++ program Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. Thanks Back to top Moonlit Guest Posted: Sun Oct 26, 2003 4:43 pm    Post subject: Re: calling GNUPLOT from a c++ program Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote Quote: Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. Strange, that shouldn't happen. Did you try to intercept all signals? Likely your program terminates because it gets a signal that it isn't expecting. Here is some code: void CCSFilt::SignalReloadFilters( int Dummy ) { GoReloadFilters = true; // Reload on next alarm signal( SIGUSR1, SignalReloadFilters ); } signal( SIGUSR1, SignalReloadFilters ); Do this for all signals and see which one is sent. Quote: Thanks Regards, Ron AF Greve. Back to top Joseph Suprenant Guest Posted: Sun Oct 26, 2003 5:27 pm    Post subject: Re: calling GNUPLOT from a c++ program are you talking to me? I don't get it "Moonlit" <alt.spam (AT) jupiter (DOT) universe> wrote Quote: Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote in message news:ARRmb.35086$%a2.6446 (AT) twister (DOT) nyroc.rr.com... Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. Strange, that shouldn't happen. Did you try to intercept all signals? Likely your program terminates because it gets a signal that it isn't expecting. Here is some code: void CCSFilt::SignalReloadFilters( int Dummy ) { GoReloadFilters = true; // Reload on next alarm signal( SIGUSR1, SignalReloadFilters ); } signal( SIGUSR1, SignalReloadFilters ); Do this for all signals and see which one is sent. Thanks Regards, Ron AF Greve. Back to top Moonlit Guest Posted: Sun Oct 26, 2003 6:40 pm    Post subject: Re: calling GNUPLOT from a c++ program Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote Quote: are you talking to me? Yes. Quote: I don't get it What I meant is that your program shouldn't terminate when it uses the system command. Likely that your program receives a signal. Some signals may terminate (abort) your program when you do not intercept them. Use "man signal" (I believe it is man 5 signal but am not sure) to see the signals that might be sent. Try to intercept them so they do not terminate your program. This you can do with the following code. void SignalCHLD( int Dummy ) { signal( SIGCHLD, SignalCHLD ); fprintf( stderr, "SIGCHLD received" ); // Not actually allowed normally, but will work most of the time. } signal( SIGCHLD, SignalCHLD ); // Do this for all possible signals! system( "gnuplot" ); Do this for all signals and see what signals your program receives. Regards, Ron AF Greve. Quote: "Moonlit" <alt.spam (AT) jupiter (DOT) universe> wrote in message news:3f9bf9bd$0$58713$e4fe514c (AT) news (DOT) xs4all.nl... Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote in message news:ARRmb.35086$%a2.6446 (AT) twister (DOT) nyroc.rr.com... Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. Strange, that shouldn't happen. Did you try to intercept all signals? Likely your program terminates because it gets a signal that it isn't expecting. Here is some code: void CCSFilt::SignalReloadFilters( int Dummy ) { GoReloadFilters = true; // Reload on next alarm signal( SIGUSR1, SignalReloadFilters ); } signal( SIGUSR1, SignalReloadFilters ); Do this for all signals and see which one is sent. Thanks Regards, Ron AF Greve. Back to top Joseph Suprenant Guest Posted: Sun Oct 26, 2003 7:13 pm    Post subject: Re: calling GNUPLOT from a c++ program well my original problem still exists how do i start GNUPLOT from my C++ program? "Moonlit" <alt.spam (AT) jupiter (DOT) universe> wrote Quote: Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote in message news:NtTmb.82096$Hs.60115 (AT) twister (DOT) nyroc.rr.com... are you talking to me? Yes. I don't get it What I meant is that your program shouldn't terminate when it uses the system command. Likely that your program receives a signal. Some signals may terminate (abort) your program when you do not intercept them. Use "man signal" (I believe it is man 5 signal but am not sure) to see the signals that might be sent. Try to intercept them so they do not terminate your program. This you can do with the following code. void SignalCHLD( int Dummy ) { signal( SIGCHLD, SignalCHLD ); fprintf( stderr, "SIGCHLD received" ); // Not actually allowed normally, but will work most of the time. } signal( SIGCHLD, SignalCHLD ); // Do this for all possible signals! system( "gnuplot" ); Do this for all signals and see what signals your program receives. Regards, Ron AF Greve. "Moonlit" <alt.spam (AT) jupiter (DOT) universe> wrote in message news:3f9bf9bd$0$58713$e4fe514c (AT) news (DOT) xs4all.nl... Hi, "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> wrote in message news:ARRmb.35086$%a2.6446 (AT) twister (DOT) nyroc.rr.com... Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. Strange, that shouldn't happen. Did you try to intercept all signals? Likely your program terminates because it gets a signal that it isn't expecting. Here is some code: void CCSFilt::SignalReloadFilters( int Dummy ) { GoReloadFilters = true; // Reload on next alarm signal( SIGUSR1, SignalReloadFilters ); } signal( SIGUSR1, SignalReloadFilters ); Do this for all signals and see which one is sent. Thanks Regards, Ron AF Greve. Back to top Frank Schmitt Guest Posted: Tue Oct 28, 2003 9:35 am    Post subject: Re: calling GNUPLOT from a c++ program "Joseph Suprenant" <laclac01 (AT) yahoo (DOT) com> writes: Quote: well my original problem still exists how do i start GNUPLOT from my C++ program? Please don't top post. Using system() is the right way to call an external program like gnuplot from C++ - if it doesn't work properly, your problem must lie elsewhere. Post some code. regards frank -- Frank Schmitt 4SC AG phone: +49 89 700763-0 e-mail: frankNO DOT SPAMschmitt AT 4sc DOT com Back to top Christian Gollwitzer Guest Posted: Fri Oct 31, 2003 8:07 am    Post subject: Re: calling GNUPLOT from a c++ program Joseph Suprenant wrote: Quote: Hello all, I have a C++ program, it does some calculations on things and then prints out a file in the format in which GNUPLOT can use. So my question is how would i call GNUPLOT from my C++ program. I know in some operating systems you can do system("gnuplot"); system is useless since then you can't pass any commands to GNUplot Quote: But not with red hat 7.3. So could some kind soul help me out? After it starts up GNUPLOT my program will terminate. I've done this on Linux using the popen() function (which is not standard C++, but POSIX-standard) class GNUplot { public: GNUplot() throw(string); ~GNUplot(); void operator ()(const string& command); // send any command to gnuplot protected: FILE *gnuplotpipe; }; GNUplot::GNUplot() throw(string) { gnuplotpipe=popen("gnuplot","w"); if (!gnuplotpipe) { throw("Gnuplot not found !"); } } GNUplot::~GNUplot() { fprintf(gnuplotpipe,"exitn"); pclose(gnuplotpipe); } void GNUplot::operator() (const string& command) { fprintf(gnuplotpipe,"%sn",command.c_str()); fflush(gnuplotpipe); // flush is necessary, nothing gets plotted else }; You simply construct one object and invoke it with operator () like GNUplot plotter; plotter("plot sin(x)"); Note that GNUplot will be killed as soon as your program terminates. So you need to wait for keystroke or similar, otherwise you will only see short flashing of the graph. If you need that the graph window stays on screen after your pragram fnished, then instead of "gnuplot" in the constructor invoke "gnuplot -persist". -- Vale ! Christianus Auriocus Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         C++Talk.NET Forum Index -> C++ language (comp.lang.c++) All times are GMT Page 1 of 1   Jump to: Select a forum C/C++----------------C LanguageC Language (Moderated)C++ Language (Moderated)C++ language (comp.lang.c++)C++ language, library and standards Non-English C/C++ Newsgroups----------------C++ (German)C++ (French)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.