Message150877
After a call to fdlistdir(), another call to fdlistdir() on the same file handle (but using a different FD, since the FD passed to fdlistdir() is closed) will return an empty list:
"""
$ cat ~/test_fdlistdir.py
import os
import sys
fd = os.open(sys.argv[1], os.O_RDONLY)
print(os.fdlistdir(os.dup(fd)))
print(os.fdlistdir(os.dup(fd)))
os.close(fd)
$ ./python ~/test_fdlistdir.py /tmp/
['pulse-B1FebW397VI5', 'ksocket-kdm', 'etc', 'kde-cf', 'ksocket-cf', 'test_posix.py', '.X0-lock', 'kde-kdm', 'akonadi-cf.k6y52j', 'ssh-iSFleEAS1243', '.ICE-unix', '.X11-unix']
[]
"""
That's because fdopendir()/readdir doesn't reset the FD offset.
It's documented by POSIX:
"""
The file offset associated with the file descriptor at the time of the call determines which entries are returned.
"""
That's rather suprising (I got bitten while trying to write a test for #13734).
I see two options:
1. rewind the directory stream in fdlistdir()
2. document this
Here's a patch for option 1. |
|
Date |
User |
Action |
Args |
2012-01-08 16:26:26 | neologix | set | recipients:
+ neologix, pitrou, rosslagerwall |
2012-01-08 16:26:26 | neologix | set | messageid: <1326039986.48.0.995838424483.issue13739@psf.upfronthosting.co.za> |
2012-01-08 16:26:25 | neologix | link | issue13739 messages |
2012-01-08 16:26:25 | neologix | create | |
|