--- libESMTP-1.1.0.orig/smtp-api.c	2021-06-04 18:18:50.000000000 +0200
+++ libESMTP-1.1.0/smtp-api.c	2026-05-19 21:32:35.567307881 +0200
@@ -20,6 +20,8 @@
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#define _BSD_SOURCE
+
 #include <config.h>
 
 #include <stdarg.h>
