diff --git a/ares/ares_process.c b/ares/ares_process.c
index 83b407077..c050308f0 100644
--- a/ares/ares_process.c
+++ b/ares/ares_process.c
@@ -33,6 +33,9 @@
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
 #endif
 
 #include <string.h>
diff --git a/ares/configure.ac b/ares/configure.ac
index e3a9c968a..6f5100b23 100644
--- a/ares/configure.ac
+++ b/ares/configure.ac
@@ -65,6 +65,7 @@ AC_CHECK_HEADERS(
        sys/time.h \
        sys/select.h \
        sys/socket.h \
+       sys/ioctl.h \
        winsock.h \
        netinet/in.h \
        net/if.h \