+<HTML>
+<HEAD>
+ <TITLE>IO::AtomicFile 2.101</TITLE>
+</HEAD>
+<BODY
+ bgcolor="#FFFFFF" link="#CC3366" vlink="#993366" alink="#FF6666">
+<FONT FACE="sans-serif" SIZE=-1><A HREF="http://www.zeegee.com" TARGET="_top"><IMG SRC="icons/zeegee.gif" ALT="ZeeGee Software" ALIGN="RIGHT" BORDER="0"></A><A NAME="__TOP__"><H1>IO::AtomicFile 2.101</H1>
+</A><UL>
+<LI> <A NAME="menu:NAME"><A HREF="#NAME">NAME</A></A>
+<LI> <A NAME="menu:SYNOPSIS"><A HREF="#SYNOPSIS">SYNOPSIS</A></A>
+<LI> <A NAME="menu:DESCRIPTION"><A HREF="#DESCRIPTION">DESCRIPTION</A></A>
+<LI> <A NAME="menu:AUTHOR"><A HREF="#AUTHOR">AUTHOR</A></A>
+<LI> <A NAME="menu:REVISION"><A HREF="#REVISION">REVISION</A></A>
+</UL>
+
+
+<P><HR>
+<A NAME="NAME"><H2><A HREF="#__TOP__"><IMG SRC="icons/h1bullet.gif" ALT="Top" BORDER="0"></A> NAME</H2></A>
+
+
+<P>IO::AtomicFile - write a file which is updated atomically
+
+
+
+<P><HR>
+<A NAME="SYNOPSIS"><H2><A HREF="#__TOP__"><IMG SRC="icons/h1bullet.gif" ALT="Top" BORDER="0"></A> SYNOPSIS</H2></A>
+
+<FONT SIZE=3 FACE="courier"><PRE>
+ use IO::AtomicFile;
+</PRE></FONT>
+<FONT SIZE=3 FACE="courier"><PRE>
+ ### Write a temp file, and have it install itself when closed:
+ my $FH = IO::AtomicFile->open("bar.dat", "w");
+ print $FH "Hello!\n";
+ $FH->close || die "couldn't install atomic file: $!";
+</PRE></FONT>
+<FONT SIZE=3 FACE="courier"><PRE>
+ ### Write a temp file, but delete it before it gets installed:
+ my $FH = IO::AtomicFile->open("bar.dat", "w");
+ print $FH "Hello!\n";
+ $FH->delete;
+</PRE></FONT>
+<FONT SIZE=3 FACE="courier"><PRE>
+ ### Write a temp file, but neither install it nor delete it:
+ my $FH = IO::AtomicFile->open("bar.dat", "w");
+ print $FH "Hello!\n";
+ $FH->detach;
+</PRE></FONT>
+
+
+<P><HR>
+<A NAME="DESCRIPTION"><H2><A HREF="#__TOP__"><IMG SRC="icons/h1bullet.gif" ALT="Top" BORDER="0"></A> DESCRIPTION</H2></A>
+
+
+<P>This module is intended for people who need to update files
+reliably in the face of unexpected program termination.
+
+
+<P>For example, you generally don't want to be halfway in the middle of
+writing <I>/etc/passwd</I> and have your program terminate! Even
+the act of writing a single scalar to a filehandle is <I>not</I> atomic.
+
+
+<P>But this module gives you true atomic updates, via rename().
+When you open a file <I>/foo/bar.dat</I> via this module, you are <I>actually</I>
+opening a temporary file <I>/foo/bar.dat..TMP</I>, and writing your
+output there. The act of closing this file (either explicitly
+via close(), or implicitly via the destruction of the object)
+will cause rename() to be called... therefore, from the point
+of view of the outside world, the file's contents are updated
+in a single time quantum.
+
+
+<P>To ensure that problems do not go undetected, the "close" method
+done by the destructor will raise a fatal exception if the rename()
+fails. The explicit close() just returns undef.
+
+
+<P>You can also decide at any point to trash the file you've been
+building.
+
+
+
+<P><HR>
+<A NAME="AUTHOR"><H2><A HREF="#__TOP__"><IMG SRC="icons/h1bullet.gif" ALT="Top" BORDER="0"></A> AUTHOR</H2></A>
+
+
+<P>Eryq (<I><FILE><A HREF="mailto:eryq@zeegee.com">eryq@zeegee.com</A></FILE></I>).
+President, ZeeGee Software Inc (<I><FILE><A HREF="http://www.zeegee.com">http://www.zeegee.com</A></FILE></I>).
+
+
+
+<P><HR>
+<A NAME="REVISION"><H2><A HREF="#__TOP__"><IMG SRC="icons/h1bullet.gif" ALT="Top" BORDER="0"></A> REVISION</H2></A>
+
+
+<P>$Revision: 2.101 $
+
+<P><HR>
+<ADDRESS><FONT SIZE=-1>
+Generated Sun Dec 21 13:54:37 2003 by cvu_pod2html
+</FONT></ADDRESS>
+</FONT></BODY>
+</HTML>
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