HEllo,
Bob Dubner wrote on gcc@ > > Thus, the statement > > CALL "foo" > > might be the equivalent, implemented in C, of > > extern <type> foo(...); //External reference > foo(); > > or > > static <type> foo(...); // Forward reference to a static > function > foo(); > > At the point of the CALL, we don't know which it's going to be. > > This is further complicated by COBOL being able to do something that C can't: > > CALL call_me > > If C could do it, it would look like this: > > char call_me[] = "foo"; > call_me(); // I told you C can't do it. > If you restrict the GCC compiler and the compiled program to run on a Linux (or POSIX) operating system, the dlsym(3) function is doing that (on global functions only): fetching a function pointer from the string name of that global function. https://man7.org/linux/man-pages/man3/dlsym.3.html https://man7.org/linux/man-pages/man3/dlopen.3.html (you might consider generating unique C identifiers with some random generator) Of course, dlsym(3) is computationally costly, you may want to cache the result. And Cobol GCC experts (I am not one) could of course consider either generating code with libgccjit (it is now inside GCC) or perhaps use GNU lightning to generate machine code. https://www.gnu.org/software/lightning/ Experimentally dlopen can be used many thousands of times (and with enough RAM perhaps hundred thousands of times). See https://github.com/bstarynk/misc-basile/blob/master/manydl.c Regards -- Basile STARYNKEVITCH <bas...@starynkevitch.net> 8 rue de la Faïencerie http://starynkevitch.net/Basile/ 92340 Bourg-la-Reine https://github.com/bstarynk France https://github.com/RefPerSys/RefPerSys
