fsync(): Implemented for Windows, via calling MS _commit. This counts

as "a bug" because there's no other way in core Python to ensure that
bytes written are actually on disk.  At least ZODB wants this guarantee,
for robustness against crashes.

diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index 3d0b4051bd3feb1d0b3669f6be997996aeabf5db..7a6383f2a5dda9143fbbd0329f2624ed0d9526ac 100644 (file)
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -433,8 +433,15 @@ Availability: \UNIX.
 \end{funcdesc}
 
 \begin{funcdesc}{fsync}{fd}
-Force write of file with filedescriptor \var{fd} to disk.
-Availability: \UNIX.
+Force write of file with filedescriptor \var{fd} to disk.  On \UNIX,
+this calls the native \cfunction{fsync()} function; on Windows, the
+MS \cfunction{_commit()} function.
+
+If you're starting with a Python file object \var{f}, first do
+\code{\var{f}.flush()}, and then do \code{os.fsync(\var{f}.fileno()},
+to ensure that all internal buffers associated with \var{f} are written
+to disk.
+Availability: \UNIX, and Windows starting in 2.2.3.
 \end{funcdesc}
 
 \begin{funcdesc}{ftruncate}{fd, length}

diff --git a/Misc/NEWS b/Misc/NEWS
index b22a277c95052d4f743234d5455c93dc5a6494e5..ed690b5cb0fd723ee0bdcc2545396399e6e4343f 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -2,6 +2,10 @@ What's New in Python 2.2.3 ?
 Release date: XX-XXX-2003
 ============================
 
+- Implemented os.fsync() for Windows, where it calls the MS _commit()
+  function.  Before, there was no way in core Python to ensure file
+  writes actually showed up on disk when necessary.
+
 - Make all the strip, lstrip, rstrip functions/methods on
   string/unicode/UserString consistent by adding and/or
   documenting the chars parameter.  The chars parameter

diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index f41d42dc8e474fed9568ac389a62292252de4e77..a070ea6be7ec56d70c5beae04e8e4975c5f9d26d 100644 (file)
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -72,6 +72,8 @@ corresponding Unix manual entries for more information on calls.";
 #else
 #ifdef _MSC_VER                /* Microsoft compiler */
 #define HAVE_GETCWD     1
+#define HAVE_FSYNC     1
+#define fsync _commit
 #ifdef MS_WIN32
 #define HAVE_SPAWNV    1
 #define HAVE_EXECV      1