int chown (char const *file_name, uid_t owner, gid_t group);
int rmdir (char const *file_name);
-#define S_IFMT 0170000
+#define S_IFCHR 0020000
#define S_IFDIR 0040000
+#define S_IFBLK 0060000
#define S_IFREG 0100000
#define S_IFLNK 0120000
+#define S_IFMT 0170000
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)