[PATCH 12 of 23] mx_ops: add "open" callback

[Damien Riegel]

# HG changeset patch
# User Damien Riegel <damien.rie...@gmail.com>
# Date 1462473575 14400
#      Thu May 05 14:39:35 2016 -0400
# Node ID c5e145e87110d5d5dc34cb5005040b424b06ae69
# Parent  5a9939d77f263a6fae4917734a2121fc2bd740ca
mx_ops: add "open" callback

This is the callback that will be called to open a mailbox.

diff -r 5a9939d77f26 -r c5e145e87110 mutt.h
--- a/mutt.h    Thu May 05 14:27:31 2016 -0400
+++ b/mutt.h    Thu May 05 14:39:35 2016 -0400
@@ -872,6 +872,7 @@
 
 struct mx_ops {
   int (*probe)(const char *path);
+  int (*open)(struct _context *);
   int (*close)(struct _context *);
 
 };