On Fri, Oct 23, 2009 at 7:02 AM, Craig Ringer <craig@xxxxxxxxxxxxxxxxxxxxx> wrote: > Massa, Harald Armin wrote: >> Ambarsih, >> >>> // add.cpp : Defines the entry point for the DLL application. >> >> are you sure that you using the C-Compiler and not the c++ compiler? >> As much as I know about defaults, that will be a C++ compiled >> function, which is something totally different then a C compiled >> function. (and, to my knowledge, a C++ function is not easily callable >> by PostgreSQL) > > So long as the function uses C linkage (extern "C") it'll be callable > directly from C++ using dlopen(), LoadLibrary, etc. > > A C++ function is callable from C via function pointer even if it has > C++ linkage, though the C calling convention declared must handle stack > management, parameter passing and return value popping in the same way > the C++ calling convention on that compiler does. That means that it's > unsafe to call a __thiscall C++ member function from C, but otherwise > it's generally fine so long as the C and C++ compilers default to the > same calling convention or you explicitly specify it on both ends. exactly...also c++ exceptions are incompatible with postgres exceptions iirc, and it's highly advisable to avoid using threads.. also there are a couple of keyword conflicts that are annoying (those may have been fixed). those gotchas aside, putting c++ in the backend is trivially done if you understand difference between c and c++ linkage. merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
