diff --git a/src/main.c b/src/main.c
index 0e8e82c..cca53fe 100644
--- a/src/main.c
+++ b/src/main.c
@@ -76,6 +76,10 @@
 // Various parameters passed between main() and other functions.
 static mparm_T	params;
 
+#ifdef _IOLBF
+static void *s_vbuf = NULL;		// buffer for setvbuf()
+#endif
+
 #ifndef NO_VIM_MAIN	// skip this for unittests
 
 static char_u *start_dir = NULL;	// current working dir on startup
@@ -353,10 +357,14 @@
     check_tty(&params);
 
 #ifdef _IOLBF
-    // Ensure output works usefully without a tty: buffer lines instead of
-    // fully buffered.
     if (silent_mode)
-	setvbuf(stdout, NULL, _IOLBF, 0);
+    {
+	// Ensure output works usefully without a tty: buffer lines instead of
+	// fully buffered.
+	s_vbuf = malloc(BUFSIZ);
+	if (s_vbuf != NULL)
+	    setvbuf(stdout, s_vbuf, _IOLBF, BUFSIZ);
+    }
 #endif
 
     // This message comes before term inits, but after setting "silent_mode"
@@ -1027,6 +1035,21 @@
 	;
 }
 
+#if defined(EXITFREE) || defined(PROTO)
+    void
+free_vbuf(void)
+{
+# ifdef _IOLBF
+    if (s_vbuf != NULL)
+    {
+	setvbuf(stdout, NULL, _IONBF, 0);
+	free(s_vbuf);
+	s_vbuf = NULL;
+    }
+# endif
+}
+#endif
+
 #if defined(FEAT_GUI) || defined(PROTO)
 /*
  * If a --gui-dialog-file argument was given return the file name.