translating C++ library to C#

[winthux]

I'm trying to use the library in c++ by using [DllImport("libr ary.dll")] but
it requires some specific structures and macros:

#define gg_common_head( x) \

int fd; /* podgl?dany deskryptor */ \

int check; /* sprawdzamy zapis czy odczyt */ \

int state; /* aktualny stan maszynki */ \

int error; /* kod b³êdu dla GG_STATE_ERROR */ \

int type; /* rodzaj sesji */ \

int id; /* identyfikator */ \

int timeout; /* sugerowany timeout w sekundach */ \

int (*callback)(x*) ; /* callback przy zmianach */ \

void (*destroy)(x*); /* funkcja niszczenia */

I have problem with this macro, how should it write in C# ? And one more
question... If in c++ structure is defined in this way:

struct some_struct {

int a;

char * b;

struct another_struct;

}

can I replace this ???

struct some_struct {

int a;

IntPtr b;

struct another_struct;

}

Sorry about my english.

Best regards,

Winthux