Hi,

after having created/compiled my own external, I tried to instal it in /usr/lib/pd/externals.... but with no luck

then I installed it manualy in my home folder ~/pd-externals/main/main.pd-linux

pd found it, but complains "main_setup" is not found, although it is there

here is a dump of the library

http://i.imgur.com/SWpwZxU.png

I compiled it doing this

g++ -Wall -c "main.c" -I"/usr/include/pd" -DPD -DVERSION='"0.0"' -fPIC -O6 -funroll-loops -fomit-frame-pointer -W -g -o "main.o"
g++ -Wall -rdynamic -shared -fPIC -Wl,-rpath,"\$ORIGIN",--enable-new-dtags -o "main.pd_linux" "main.o" -lc
chmod a-x "main.pd_linux"

can someone find what I do wrong ? Is it not supposed to work when compiled with c++ ? I prefer using c++ it has more posibilities than c

thanks

#include "/usr/include/pd/m_pd.h"

static t_class *main_class;

typedef struct _main
{
    t_object x_obj;
} t_main;

void main_bang(t_main *x)  
{  
  post("Hello world !! %p",x);  
} 

void *main_new(void)  
{  
  t_main *x = (t_main *)pd_new(main_class);  
 
  return (void *)x;  
} 

void main_setup(void)  
{  
  main_class = class_new(
        gensym("main"),  
        (t_newmethod)main_new,  
        NULL, 
        sizeof(t_main),  
        CLASS_DEFAULT,
        (t_atomtype)0);  
 
  class_addbang(main_class, main_bang);  
}

I've never coded an external in C++ but I know that you need some sort of wrapper in order to write an object in C++. Check out flext by Thomas Grill http://grrrr.org/research/software/flext/ it is supposed to do exactly that.

yeah porbably that the c++ compiler dont create the same function signature as c
thansk

ok the code compiled fine and pd recognizes it
so I got potentiometers read by an ISP ADC that returns values in a nice puredata object hihi
awesome

Have you fixed it with a simple "extern C" around your main_setup function?

BTW, a bit off-topic, but it's better to include the path to the directory of the header files you need to compile your object in the Makefile (here, m_pd.h) rather than having an absolute path in your source code.

@Jojo-Lapin

just changed the extension of the file to .c and used cc to compile

I still dont agree with a nowadays'software programmed entirely in c, even on an arduino we do c++

it's 2016 for god sake puket

You can use c++ code, you just need to declare extern "C" before the setup method (as @Jojo-Lapin said). This statement prevents the C++ from name mangling and thus creating "unresolved symbols" when linking. But you can use all the c++ libraries you want in your code.