[glib] docs: Add a link to the Wikipedia page on TOCTTOU races

[Philip Withnall <pwithnall src gnome org>]

commit d3b07453ab0043797bbef4591bdc2b955a390b00
Author: Philip Withnall <withnall endlessm com>
Date:   Fri Jan 12 12:10:16 2018 +0000

    docs: Add a link to the Wikipedia page on TOCTTOU races
    
    Try and make it a bit more obvious that g_file_query_exists() is
    generally A Bad Idea.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>
    Reviewed-by: nobody

 gio/gfile.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gio/gfile.c b/gio/gfile.c
index 812b148..4405582 100644
--- a/gio/gfile.c
+++ b/gio/gfile.c
@@ -1060,7 +1060,7 @@ g_file_enumerate_children_finish (GFile         *file,
  * Utility function to check if a particular file exists. This is
  * implemented using g_file_query_info() and as such does blocking I/O.
  *
- * Note that in many cases it is racy to first check for file existence
+ * Note that in many cases it is [racy to first check for file 
existence](https://en.wikipedia.org/wiki/Time_of_check_to_time_of_use)
  * and then execute something based on the outcome of that, because the
  * file might have been created or removed in between the operations. The
  * general approach to handling that is to not check, but just do the