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>0; i++){
            //users are friends
            if((strcmp(author->friends[i]->name, target->name)==0) && author->name[i]!=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;
    }
}
assign current date and time to User target's date