[Python-bugs-list] [ python-Bugs-449880 ] File size limit exceeded causes ABEND

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Bugs item #449880, was opened at 2001-08-10 11:28
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Category: Python Interpreter Core
Group: None
>Status: Closed
>Resolution: Fixed
Priority: 5
Submitted By: Nobody/Anonymous (nobody)
Assigned to: Guido van Rossum (gvanrossum)
Summary: File size limit exceeded causes ABEND

Initial Comment:
The following code will never run to completion on
systems with a 2GB file size limit. The interpreter
exits as soon as it exceeds the file size limit.

Create a file called "testfile" that is 2GB - 1 in
size. Run the following program to observe behaviour.

#!/usr/bin/env python2
#
# Create a file called "testfile" that is 2147483647
bytes in size. Then
# run this application. The python interpreter prints
the message "File
# size limit exceeded" and exits, rather than raising
an exception. 
#
# Tested with Python-2.1.1 on Red Hat 7.2 beta (Roswell)

fp = open('testfile', 'a')

try:
	fp.write('foo')
	fp.flush()
	fp.close()
except OSError, e:
	print e

print "done"



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>Comment By: Guido van Rossum (gvanrossum)
Date: 2001-08-16 08:12

Message:
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user_id=6380

I've got no feedback.  I'm just assuming it works.

Fixed in CVS: pythonrun.c:2.145.

----------------------------------------------------------------------

Comment By: Guido van Rossum (gvanrossum)
Date: 2001-08-10 12:04

Message:
Logged In: YES 
user_id=6380

Please try this patch.

----------------------------------------------------------------------

Comment By: Guido van Rossum (gvanrossum)
Date: 2001-08-10 12:01

Message:
Logged In: YES 
user_id=6380

Yes, this is a bug.

It happens in the fp.flush() call.  This does a write() that
would cause the file size to exceed the limit, and such a
write receives a SIGXFSZ signal - a signal similar to
SIGPIPE.

A workaround is to do this before writing such a large file:

import signal
signal.signal(signal.SIGXFSZ, signal.SIG_IGN)

Python should ignore the SIGXFSZ signal, if it exists, just
like it ignores SIGPIPE.

I wonder, are there any other signals that we would want to
ignore like this?

----------------------------------------------------------------------

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