diff -r 000000000000 -r ae805ac0140d python-2.5.2/win32/Lib/test/test_largefile.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python-2.5.2/win32/Lib/test/test_largefile.py	Fri Apr 03 17:19:34 2009 +0100
@@ -0,0 +1,170 @@
+#!python
+
+#----------------------------------------------------------------------
+# test largefile support on system where this makes sense
+#
+#----------------------------------------------------------------------
+
+from test import test_support
+import os, struct, stat, sys
+
+try:
+    import signal
+    # The default handler for SIGXFSZ is to abort the process.
+    # By ignoring it, system calls exceeding the file size resource
+    # limit will raise IOError instead of crashing the interpreter.
+    oldhandler = signal.signal(signal.SIGXFSZ, signal.SIG_IGN)
+except (ImportError, AttributeError):
+    pass
+
+
+# create >2GB file (2GB = 2147483648 bytes)
+size = 2500000000L
+name = test_support.TESTFN
+
+
+# On Windows and Mac OSX this test comsumes large resources; It takes
+# a long time to build the >2GB file and takes >2GB of disk space
+# therefore the resource must be enabled to run this test.  If not,
+# nothing after this line stanza will be executed.
+if sys.platform[:3] == 'win' or sys.platform == 'darwin':
+    test_support.requires(
+        'largefile',
+        'test requires %s bytes and a long time to run' % str(size))
+else:
+    # Only run if the current filesystem supports large files.
+    # (Skip this test on Windows, since we now always support large files.)
+    f = open(test_support.TESTFN, 'wb')
+    try:
+        # 2**31 == 2147483648
+        f.seek(2147483649L)
+        # Seeking is not enough of a test: you must write and flush, too!
+        f.write("x")
+        f.flush()
+    except (IOError, OverflowError):
+        f.close()
+        os.unlink(test_support.TESTFN)
+        raise test_support.TestSkipped, \
+              "filesystem does not have largefile support"
+    else:
+        f.close()
+
+
+def expect(got_this, expect_this):
+    if test_support.verbose:
+        print '%r =?= %r ...' % (got_this, expect_this),
+    if got_this != expect_this:
+        if test_support.verbose:
+            print 'no'
+        raise test_support.TestFailed, 'got %r, but expected %r' %\
+              (got_this, expect_this)
+    else:
+        if test_support.verbose:
+            print 'yes'
+
+
+# test that each file function works as expected for a large (i.e. >2GB, do
+# we have to check >4GB) files
+
+if test_support.verbose:
+    print 'create large file via seek (may be sparse file) ...'
+f = open(name, 'wb')
+try:
+    f.write('z')
+    f.seek(0)
+    f.seek(size)
+    f.write('a')
+    f.flush()
+    if test_support.verbose:
+        print 'check file size with os.fstat'
+    expect(os.fstat(f.fileno())[stat.ST_SIZE], size+1)
+finally:
+    f.close()
+if test_support.verbose:
+    print 'check file size with os.stat'
+expect(os.stat(name)[stat.ST_SIZE], size+1)
+
+if test_support.verbose:
+    print 'play around with seek() and read() with the built largefile'
+f = open(name, 'rb')
+try:
+    expect(f.tell(), 0)
+    expect(f.read(1), 'z')
+    expect(f.tell(), 1)
+    f.seek(0)
+    expect(f.tell(), 0)
+    f.seek(0, 0)
+    expect(f.tell(), 0)
+    f.seek(42)
+    expect(f.tell(), 42)
+    f.seek(42, 0)
+    expect(f.tell(), 42)
+    f.seek(42, 1)
+    expect(f.tell(), 84)
+    f.seek(0, 1)
+    expect(f.tell(), 84)
+    f.seek(0, 2) # seek from the end
+    expect(f.tell(), size + 1 + 0)
+    f.seek(-10, 2)
+    expect(f.tell(), size + 1 - 10)
+    f.seek(-size-1, 2)
+    expect(f.tell(), 0)
+    f.seek(size)
+    expect(f.tell(), size)
+    expect(f.read(1), 'a') # the 'a' that was written at the end of file above
+    f.seek(-size-1, 1)
+    expect(f.read(1), 'z')
+    expect(f.tell(), 1)
+finally:
+    f.close()
+
+if test_support.verbose:
+    print 'play around with os.lseek() with the built largefile'
+f = open(name, 'rb')
+try:
+    expect(os.lseek(f.fileno(), 0, 0), 0)
+    expect(os.lseek(f.fileno(), 42, 0), 42)
+    expect(os.lseek(f.fileno(), 42, 1), 84)
+    expect(os.lseek(f.fileno(), 0, 1), 84)
+    expect(os.lseek(f.fileno(), 0, 2), size+1+0)
+    expect(os.lseek(f.fileno(), -10, 2), size+1-10)
+    expect(os.lseek(f.fileno(), -size-1, 2), 0)
+    expect(os.lseek(f.fileno(), size, 0), size)
+    expect(f.read(1), 'a') # the 'a' that was written at the end of file above
+finally:
+    f.close()
+
+if hasattr(f, 'truncate'):
+    if test_support.verbose:
+        print 'try truncate'
+    f = open(name, 'r+b')
+    try:
+        f.seek(0, 2)
+        expect(f.tell(), size+1)    # else we've lost track of the true size
+        # Cut it back via seek + truncate with no argument.
+        newsize = size - 10
+        f.seek(newsize)
+        f.truncate()
+        expect(f.tell(), newsize)   # else pointer moved
+        f.seek(0, 2)
+        expect(f.tell(), newsize)   # else wasn't truncated
+        # Ensure that truncate(smaller than true size) shrinks the file.
+        newsize -= 1
+        f.seek(42)
+        f.truncate(newsize)
+        expect(f.tell(), 42)        # else pointer moved
+        f.seek(0, 2)
+        expect(f.tell(), newsize)   # else wasn't truncated
+
+        # XXX truncate(larger than true size) is ill-defined across platforms
+
+        # cut it waaaaay back
+        f.seek(0)
+        f.truncate(1)
+        expect(f.tell(), 0)         # else pointer moved
+        expect(len(f.read()), 1)    # else wasn't truncated
+
+    finally:
+        f.close()
+
+os.unlink(name)