int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home, const char **shell);
int get_group_creds(const char **groupname, gid_t *gid);
+int in_gid(gid_t gid);
int in_group(const char *name);
char* uid_to_name(uid_t uid);
+char* gid_to_name(gid_t gid);
int glob_exists(const char *path);