file_truncate(): provide full "large file" support on Windows, by

dropping MS's inadequate _chsize() function.  This was inspired by
SF patch 498109 ("fileobject truncate support for win32"), which I
rejected.

libstdtypes.tex:  Someone who knows should update the availability
blurb.  For example, if it's available on Linux, it would be good to
say so.

test_largefile:  Uncommented the file.truncate() tests, and reworked to
do more.  The old comment about "permission errors" in the truncation
tests under Windows was almost certainly due to that the file wasn't open
for *write* access at this point, so of course MS wouldn't let you
truncate it.  I'd be appalled if a Unixish system did.

CAUTION:  Someone should run this test on Linux (etc) too.  The
truncation part was commented out before.  Note that test_largefile isn't
run by default.

1 files changed, 5 insertions, 1 deletions

diff --git a/Misc/NEWS b/Misc/NEWS
index 58d5a66..6611c5d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -73,7 +73,7 @@ C API
 - Because Python's magic number scheme broke on January 1st, we decided
   to stop Python development.  Thanks for all the fish!
 
-- Some of us don't like fish, so we changed Python's magic number 
+- Some of us don't like fish, so we changed Python's magic number
   scheme to a new one. See Python/import.c for details.
 
 New platforms
@@ -84,6 +84,10 @@ Tests
 
 Windows
 
+- file.truncate([newsize]) now works on Windows for all newsize values.
+  It used to fail if newsize didn't fit in 32 bits, reflecting a
+  limitation of MS _chsize (which is no longer used).
+
 - os.waitpid() is now implemented for Windows, and can be used to block
   until a specified process exits.  This is similar to, but not exactly
   the same as, os.waitpid() on POSIX systems.  If you're waiting for