Add some debug logging code to AllocateFile's failure path to log the

specific Windows error code (GetLastError).  This is a hopefully temporary
hack to try to diagnose rare failures.  Magnus Hagander

src/backend/storage/file/fd.c

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.128 2006/05/30 13:04:59 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/file/fd.c,v 1.129 2006/08/24 03:15:43 tgl Exp $
  *
  * NOTES:
  *
@@ -1278,6 +1278,20 @@ TryAgain:
 		errno = save_errno;
 	}
 
+	/*
+	 * TEMPORARY hack to log the Windows error code on fopen failures,
+	 * in hopes of diagnosing some hard-to-reproduce problems.
+	 */
+#ifdef WIN32
+	{
+		int			save_errno = errno;
+
+		elog(LOG, "Windows fopen(\"%s\",\"%s\") failed: code %lu, errno %d",
+			 name, mode, GetLastError(), save_errno);
+		errno = save_errno;
+	}
+#endif
+
 	return NULL;
 }