[svnbook commit] r1998 - trunk/src/en/book

cmpilato svnbook-dev at red-bean.com
Mon Feb 13 11:05:37 CST 2006


Author: cmpilato
Date: Mon Feb 13 11:05:35 2006
New Revision: 1998

Modified:
   trunk/src/en/book/ch02.xml

Log:
* src/en/book/ch02.xml
  Lose bogus library-book/locking analogy.


Modified: trunk/src/en/book/ch02.xml
==============================================================================
--- trunk/src/en/book/ch02.xml	(original)
+++ trunk/src/en/book/ch02.xml	Mon Feb 13 11:05:35 2006
@@ -83,19 +83,20 @@
         repository.</para>
 
       <para>Consider the scenario shown in <xref
-        linkend="svn.basic.vsn-models.problem-sharing.dia-1"/>.  Suppose we have two co-workers,
-        Harry and Sally.  They each decide to edit the same repository
-        file at the same time.  If Harry saves his changes to the
-        repository first, then it's possible that (a few moments
-        later) Sally could accidentally overwrite them with her own
-        new version of the file.  While Harry's version of the file
-        won't be lost forever (because the system remembers every
-        change), any changes Harry made <emphasis>won't</emphasis> be
-        present in Sally's newer version of the file, because she
-        never saw Harry's changes to begin with.  Harry's work is
-        still effectively lost—or at least missing from the
-        latest version of the file—and probably by accident.
-        This is definitely a situation we want to avoid!</para>
+        linkend="svn.basic.vsn-models.problem-sharing.dia-1"/>.
+        Suppose we have two co-workers, Harry and Sally.  They each
+        decide to edit the same repository file at the same time.  If
+        Harry saves his changes to the repository first, then it's
+        possible that (a few moments later) Sally could accidentally
+        overwrite them with her own new version of the file.  While
+        Harry's version of the file won't be lost forever (because the
+        system remembers every change), any changes Harry made
+        <emphasis>won't</emphasis> be present in Sally's newer version
+        of the file, because she never saw Harry's changes to begin
+        with.  Harry's work is still effectively lost—or at
+        least missing from the latest version of the file—and
+        probably by accident.  This is definitely a situation we want
+        to avoid!</para>
 
       <figure id="svn.basic.vsn-models.problem-sharing.dia-1">
         <title>The problem to avoid</title>
@@ -109,19 +110,19 @@
       <title>The Lock-Modify-Unlock Solution</title>
       
       <para>Many version control systems use a
-        <firstterm>lock-modify-unlock</firstterm> model to address
-        this problem.  In such a system, the repository allows only
-        one person to change a file at a time.  First Harry must
-        <quote>lock</quote> the file before he can begin making
-        changes to it.  Locking a file is a lot like borrowing a book
-        from the library; if Harry has locked a file, then Sally
-        cannot make any changes to it.  If she tries to lock the file,
-        the repository will deny the request.  All she can do is read
-        the file, and wait for Harry to finish his changes and release
-        his lock.  After Harry unlocks the file, his turn is over, and
-        now Sally can take her turn by locking and editing.  <xref
-        linkend="svn.basic.vsn-models.lock-unlock.dia-1"/> demonstrates this simple
-        solution.</para>
+        <firstterm>lock-modify-unlock</firstterm> model to address the
+        problem of many authors clobbering each other's work.  In this
+        model, the repository allows only one person to change a file
+        at a time.  This exclusivity policy is managed using locks.
+        Harry must <quote>lock</quote> a file before he can begin
+        making changes to it.  If Harry has locked a file, then Sally
+        cannot also lock it, and therefore cannot make any changes to
+        that file.  All she can do is read the file, and wait for
+        Harry to finish his changes and release his lock.  After Harry
+        unlocks the file, Sally can take her turn by locking and
+        editing the file.  <xref
+        linkend="svn.basic.vsn-models.lock-unlock.dia-1"/>
+        demonstrates this simple solution.</para>
       
       <figure id="svn.basic.vsn-models.lock-unlock.dia-1">
         <title>The lock-modify-unlock solution</title>




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