Regen.

configure

@@ -17153,6 +17153,42 @@ printf "%s\n" "#define HAVE_TCP_INFO_SND_WND 1" >>confdefs.h
 
 fi
 
+# Check for IPPROTO_MPTCP (Linux)
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking MPTCP protocol" >&5
+printf %s "checking MPTCP protocol... " >&6; }
+if test ${iperf3_cv_header_ipproto_mptcp+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <netinet/in.h>
+int
+main (void)
+{
+int foo = IPPROTO_MPTCP;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"
+then :
+  iperf3_cv_header_ipproto_mptcp=yes
+else case e in #(
+  e) iperf3_cv_header_ipproto_mptcp=no ;;
+esac
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
+esac
+fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $iperf3_cv_header_ipproto_mptcp" >&5
+printf "%s\n" "$iperf3_cv_header_ipproto_mptcp" >&6; }
+if test "x$iperf3_cv_header_ipproto_mptcp" = "xyes"; then
+
+printf "%s\n" "#define HAVE_IPPROTO_MPTCP 1" >>confdefs.h
+
+fi
+
 # Check if we need -lrt for clock_gettime
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for library containing clock_gettime" >&5
 printf %s "checking for library containing clock_gettime... " >&6; }

src/iperf_config.h.in

@@ -33,6 +33,9 @@
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
+/* Have MPTCP protocol. */
+#undef HAVE_IPPROTO_MPTCP
+
 /* Have IP_DONTFRAG sockopt. */
 #undef HAVE_IP_DONTFRAG