[PATCH] Re: 'The Three Meanings of "Lock"' += svn:sync-lock ?

[Daniel Shahaf]

Daniel Shahaf wrote on Wed, Mar 09, 2016 at 13:24:41 +0000:
> Concerning the 'The Three Meanings of "Lock"' box:
> .
>     http://svnbook.red-bean.com/nightly/en/svn.advanced.locking.html#svn.advanced.locking.meanings
> .
> Should that box mention svnsync locks as well?

Here's a patch.  I've mostly kept to the template of the existing
entries.

TODO: the text doesn't yet mention 'svnrdump load' locks.

[[[
* ch03-advanced-topics.xml
  (#svn.advanced.locking.meaning): Document svnsync locks as well.
]]]

[[[
Index: ch03-advanced-topics.xml
===================================================================
--- ch03-advanced-topics.xml    (revision 5128)
+++ ch03-advanced-topics.xml    (working copy)
@@ -4001,12 +4001,12 @@ $
       all of these facets of the larger locking feature.</para>
 
     <sidebar id="svn.advanced.locking.meanings">
-      <title>The Three Meanings of <quote>Lock</quote></title>
+      <title>The Four Meanings of <quote>Lock</quote></title>
 
       <para>In this section, and almost everywhere in this book, the
         words <quote>lock</quote> and <quote>locking</quote> describe
         a mechanism for mutual exclusion between users to avoid
-        clashing commits.  Unfortunately, there are two other sorts
+        clashing commits.  Unfortunately, there are other sorts
         of <quote>lock</quote> with which Subversion, and therefore
         this book, sometimes needs to be concerned.</para>
 
@@ -4035,6 +4035,18 @@ $
         be <quote>wedged,</quote> as described in
         <xref linkend="svn.berkeleydb.maintenance.recovery" />.</para>
 
+      <para>
+        <indexterm>
+          <primary>locks</primary>
+          <secondary>svnsync</secondary>
+        </indexterm>Finally, there are <firstterm>svnsync
+        locks</firstterm>, which effect mutual exclusion between multiple
+        instances of the <command>svnsync</command> command that write
+        to the same mirror of a repository.  This is the sort of lock
+        implemented by the <literal>svn:sync-lock</literal> revision
+        property, as described in <xref
+        linkend="svn.reposadmin.maint.replication.svnsync" />.</para>
+
       <para>You can generally forget about these other kinds of locks
         until something goes wrong that requires you to care about
         them.  In this book, <quote>lock</quote> means the first sort
]]]

Cheers,

Daniel

> (These are the svn_ra__get_operational_lock() locks that svnsync takes
> using the svn:sync-lock revprop, exposed in the UI through the
> --disable-locks/--steal-lock options to 'svnsync sync'.  Note 'svnrdump
> load' also uses this kind of operational lock.)