Mike Parker wrote:
Heinz wrote:
torhu Wrote:
On 10.02.2009 19:51, Heinz wrote:
Heinz Wrote:
I attached a rar file with the sources just to see what i'm talking
about. The example is from the DMD site. Included is the extern D
(ok) and the extern C (fails). To compile open "compile.bat" and to
run the programs use "run.bat".
Try this:
alias extern (C) void function(void*) MyDLL_Initialize_fp;
alias extern (C) void function() MyDLL_Terminate_fp;
alias extern (C) MyClass function() getMyClass_fp;
Haha! cool man, thanx, it works.
I never though it could be the type but adding extern(C), the program
treats variables as C function pointers. I had no idea at all that i
can create extern(C) variables to be trated as C type. I learned
something new today!
Thanks again.
It doesn't affect normal variables. Calling a function through a
function pointer, the calling convention still must be known in order
for parameters to be properly passed. So any time you define a function
pointer to point to a C function or to pass to a C API as a callback, it
must have the proper extern linkage.
Actually, extern(C) does affect normal variables. In particular, it
affects their name mangling. (And if the type of the variable includes a
'raw' function pointer type (not an alias/typedef to one), I'm pretty
sure it also modifies that type to use a C calling convention function
pointer type)
The example above, though, does not directly affect any variables
because they're only alias declarations.
