reading a global external (C) char* in D2

[Graham Fawcett]

On Sun, 18 Apr 2010 19:14:33 +0200, Lars T. Kyllingstad wrote:

> Graham Fawcett wrote:
>> Hi folks,
>> 
>> I'm having trouble reading an external(C) global value in D2. I think
>> I'm using __gshared properly to sidestep the TLS issues, but I'm still
>> getting an incorrect result.
>> 
>> Consider the two following programs, one in C, the other D2:
>> 
>>     // testc.c
>>     #include <stdio.h>
>>     extern char *gdbm_version;	// or #include <gdbm.h>
>> 
>>     int main() {
>>       printf("VERSION (C): %s.\n", gdbm_version);
>>     }
>> 
>> $ gcc -o testc testc.c -lgdbm && ./testc VERSION (C): GDBM version
>> 1.8.3. 10/15/2002 (built Nov  5 2008 02:36:47).
>> 
>>     // testd.d
>>     import std.stdio;
>>     import std.conv;
>> 
>>     __gshared extern (C) char *gdbm_version;
>> 
>>     void main() {
>>       string v = to!string(gdbm_version);
>>       writef("VERSION (D): %s.\n", v);
>>     }
>> 
>> $ dmd testd.d -L-lgdbm && ./testd
>> VERSION (D): .
>> 
>> Am I doing something wrong?
>> 
>> Thanks,
>> Graham
> 
> 
> Try adding a second 'extern':
> 
>    extern(C) extern __gshared char* gdbm_version;

That did it! Thank you. I have much to learn.

Cheers,
Graham


> 
> -Lars