MarkMessageRead
MarkMessageRead(fRef, flag);
MarkMessageRead(fRef, B_SEEN);
MarkMessageRead(fRef, B_READ);
MarkMessageRead(fRef, B_SEEN);
MarkMessageRead(&orgRef, B_READ);
MarkMessageRead(fRef, B_READ);
MarkMessageRead(fRef, B_SEEN);
void MarkMessageRead(entry_ref* message,