On 05/19/2015 05:59 AM, Skip Montanaro wrote:
Due to presumed bugs in an underlying library over which I have no control, I'm
considering a restart in the wee hours of the morning. The basic fork/exec
dance is not a problem, but how do I discover
all the open file descriptors in the new child process to make sure they get
closed? Do I simply start at fd 3 and call os.close() on everything up to some
largish fd number? Some of these file
descriptors will have been opened by stuff well below the Python level, so I
don't know them a priori.
Pandaemonium [1] (and I believe Ben Finney's daemon [2]) use something akin to
the following:
def close_open_files(exclude):
max_files = resource.getrlimit(resource.RLIMIT_NOFILE)[1]
keep = set()
for file in exclude:
if isinstance(file, baseint):
keep.add(file)
elif hasattr(file, 'fileno'):
keep.add(file.fileno())
else:
raise ValueError(
'files to not close should be either an file descriptor, '
'or a file-type object, not %r (%s)' % (type(file), file))
for fd in range(max_files, -1, -1):
if fd in keep:
continue
try:
os.close(fd)
except OSError:
exc = sys.exc_info()[1]
if exc.errno == errno.EBADF:
continue
raise
So, yeah, basically a brute-force method.
--
~Ethan~
[1] https://pypi.python.org/pypi/pandaemonium
[2] https://pypi.python.org/pypi/python-daemon
--
https://mail.python.org/mailman/listinfo/python-list
