---
 imap/src/mlock/mlock.c |    1 +
 1 file changed, 1 insertion(+)

Index: alpine-2.11/imap/src/mlock/mlock.c
===================================================================
--- alpine-2.11.orig/imap/src/mlock/mlock.c
+++ alpine-2.11/imap/src/mlock/mlock.c
@@ -28,6 +28,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <unistd.h>
 #include <stdio.h>
 #include <sysexits.h>
 #include <syslog.h>