I'm currenlty experimenting about binding to C.
I have :
C-library:

mylib.h:

void libprintme(char *s);

mylib.c:

#include <stdio.h>
#include "mylib.h"
void libprintme(char *s){printf("%s",s);}

main.d:

extern(C) @nogc nothrow {
	void libprintme(char *s);
    alias pprintme=void function(char *s);
    __gshared pprintme cprintme=&libprintme;

}

extern(D) {
	void dprintme(string ds){
		alias dstring=string;
		alias cstring=char *;
		import std.conv: to,castFrom;
		cstring cs=castFrom!dstring.to!cstring(ds);
		(*cprintme)(cs);
		import core.stdc.stdio: printf;
		printf("World");
	}

Can this procedure be used for larger C-libraries ?
What is good , what is bad , what can be better. Feel free to elaborate ?

(It's the C-preprocessor with macro expansion which gives me sometimes a bit of a headache.)

void main(){dprintme("Hello\n");}
}

On Sunday, 24 April 2022 at 15:13:15 UTC, Alain De Vos wrote:

void libprintme(char *s);

#include <stdio.h>
#include "mylib.h"
void libprintme(char *s){printf("%s",s);}

Why not just

extern(C) @nogc nothrow {
    void libprintme(char *s);
    alias cprintme = libprintme;
}

?

The function pointer looks totally superfluous to me.