+ [hooks]
+ changegroup = hg update >&2 && ikiwiki --setup path.to.setup.file --refresh
+ post-commit = path.to.the.mercurial.wrapper
+
+-----
+
+I have no idea when the deadlock will happen. --[[users/weakish]]
+
+> For the deadlock to occur, a edit has to be made via the web.
+>
+> Ikiwiki,
+> running as a CGI, takes a lock on the wiki, and commits the edit,
+> continuing to run in the background, with the lock still held.
+> When the edit is committed, the hg hook runs, running `ikwiki --refresh`.
+> Nearly the first thing that process does it try to lock the wiki..
+> which is already locked. This lock is taken in a blocking manner,
+> thus the deadlock -- the cgi is waiting for the commit to finish before
+> dropping the lock, and the commit is blocked waiting for the lock to be
+> released.
+>
+> --post-commit avoids this problem by checking if the cgi is running
+> and avoiding doing anything in that case. (While still handing the
+> refresh if the commit was not made by the CGI.)
+> So in that case, the commit finishes w/o ikiwiki doing anything,
+> and the ikiwiki CGI handles the wiki refresh.
+> --[[Joey]]