int greylist_initialize(const char *directory, const char *prefix);
bool try_greylist(const char *sender, const char *c_addr,
const char *c_name, const char *rcpt);
int greylist_initialize(const char *directory, const char *prefix);
bool try_greylist(const char *sender, const char *c_addr,
const char *c_name, const char *rcpt);