int make_post(const User *author, User *target, char *contents) {
    //check if users are friends
     if(author != NULL && target != NULL){
        for(int i=0; i<MAX_FRIENDS; i++){
            //users are friends
            if(author->friends[i]!=0){
                if((strcmp(author->friends[i]->name, target->name)==0)){
                    Post *new_post = malloc(sizeof(Post));
                    new_post->contents = contents;
                    strncpy(new_post->author, author->name, sizeof(new_post->author));
                    time_t *date = malloc(sizeof (*date));
                    time(date);
                    new_post->date= date;
                    new_post->next = target->first_post;
                    target->first_post = new_post;

                    return 0;
                }
            }
            //users aren't friends
            else{
                return 1;
            }
            
        }
    }
    else{
        return 2;
    }
}
return 0 if success