From f5f27646ee5c3033d04d86d069b6a7a6b5edb8e1 Mon Sep 17 00:00:00 2001
From: Michael Theall <pigman46@gmail.com>
Date: Mon, 5 Jun 2017 11:50:41 -0500
Subject: [PATCH] Set SO_LINGER with timeout=0 before close

Hopefully this helps with clients that don't acknowledge our close.
Thanks to TuxSH for testing with Windows Explorer.
---
 source/ftp.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/source/ftp.c b/source/ftp.c
index 8fc563c..586ba93 100644
--- a/source/ftp.c
+++ b/source/ftp.c
@@ -365,6 +365,16 @@ ftp_closesocket(int  fd,
       console_print(RED "poll: %d %s\n" RESET, errno, strerror(errno));
   }
 
+  /* set linger to 0 */
+  struct linger linger;
+  linger.l_onoff  = 1;
+  linger.l_linger = 0;
+  rc = setsockopt(fd, SOL_SOCKET, SO_LINGER,
+                  &linger, sizeof(linger));
+  if(rc != 0)
+    console_print(RED "setsockopt: SO_LINGER %d %s\n" RESET,
+                  errno, strerror(errno));
+
   /* close socket */
   rc = close(fd);
   if(rc != 0)