glibc ioctl.h has it too.
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926
#define SIOCSIFMEM 0x8920
#define SIOCGIFMTU 0x8921
#define SIOCSIFMTU 0x8922
+#define SIOCSIFNAME 0x8923
#define SIOCSIFHWADDR 0x8924
#define SIOCGIFENCAP 0x8925
#define SIOCSIFENCAP 0x8926