diff --git a/lib/if2ip.c b/lib/if2ip.c
index 988e5924a3b90aeb0d5806a075d8de55069841d3..d4cfa51810d7e5c4099301e5bd3060ac88ec74ae 100644
--- a/lib/if2ip.c
+++ b/lib/if2ip.c
@@ -77,6 +77,10 @@
 #include "memdebug.h"
 #endif
 
+#ifdef DJGPP
+#define IOCTL_3_ARGS
+#endif
+
 #define SYS_ERROR -1
 
 char *Curl_if2ip(char *interface, char *buf, int buf_size)