Defined in 2 files as a macro:

• include/uapi/linux/if_tun.h, line 25 (as a macro)
• tools/include/uapi/linux/if_tun.h, line 25 (as a macro)

Referenced in 3 files:

• drivers/net/ipvlan/ipvtap.c, line 137
• drivers/net/macvtap.c, line 133
• drivers/net/tun.c, line 2403