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POParamiko inside Python Daemon causes IOError
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copied!<p>I'm trying to execute <code>ssh</code> commands using <code>paramiko</code> from inside a python daemon process. I'm using the following implementation for the daemon: <a href="https://pypi.python.org/pypi/python-daemon/" rel="nofollow">https://pypi.python.org/pypi/python-daemon/</a></p> <p>When the program is started <code>pycrypto</code> raises an <code>IOError</code> with a <code>Bad file descriptor</code> when paramiko tries to connect. If I remove the daemon code (just uncomment the last line and comment the two above) the <code>ssh</code> connection is established as expected.</p> <p>The code for a short test program looks like this:</p> <pre><code>#!/usr/bin/env python2 from daemon import runner import paramiko class App(): def __init__(self): self.stdin_path = '/dev/null' self.stdout_path = '/dev/tty' self.stderr_path = '/dev/tty' self.pidfile_path = '/tmp/testdaemon.pid' self.pidfile_timeout = 5 def run(self): ssh = paramiko.SSHClient() ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) ssh.load_system_host_keys() ssh.connect("hostname", username="username") ssh.close() app = App() daemon_runner = runner.DaemonRunner(app) daemon_runner.do_action() #app.run() </code></pre> <p>The trace looks like this:</p> <pre><code>Traceback (most recent call last): File "./daemon-test.py", line 31, in <module> daemon_runner.do_action() File "/usr/lib/python2.7/site-packages/daemon/runner.py", line 189, in do_action func(self) File "/usr/lib/python2.7/site-packages/daemon/runner.py", line 134, in _start self.app.run() File "./daemon-test.py", line 22, in run ssh.connect("hostname", username="username") File "/usr/lib/python2.7/site-packages/paramiko/client.py", line 311, in connect t.start_client() File "/usr/lib/python2.7/site-packages/paramiko/transport.py", line 460, in start_client Random.atfork() File "/usr/lib/python2.7/site-packages/Crypto/Random/__init__.py", line 37, in atfork _UserFriendlyRNG.reinit() File "/usr/lib/python2.7/site-packages/Crypto/Random/_UserFriendlyRNG.py", line 224, in reinit _get_singleton().reinit() File "/usr/lib/python2.7/site-packages/Crypto/Random/_UserFriendlyRNG.py", line 171, in reinit return _UserFriendlyRNG.reinit(self) File "/usr/lib/python2.7/site-packages/Crypto/Random/_UserFriendlyRNG.py", line 99, in reinit self._ec.reinit() File "/usr/lib/python2.7/site-packages/Crypto/Random/_UserFriendlyRNG.py", line 62, in reinit block = self._osrng.read(32*32) File "/usr/lib/python2.7/site-packages/Crypto/Random/OSRNG/rng_base.py", line 76, in read data = self._read(N) File "/usr/lib/python2.7/site-packages/Crypto/Random/OSRNG/posix.py", line 65, in _read d = self.__file.read(N - len(data)) IOError: [Errno 9] Bad file descriptor </code></pre> <p>I'm guessing this has something to do with the stream redirection when the daemon spawns. I've tried to set them all to <code>/dev/tty</code> or even to a normal file but nothing works.</p> <p>When I run the program with <code>strace</code> I can see that something tries to close a file twice and that's when I get the error. But I couldn't find out which file the descriptor actually points to (<code>strace</code> shows a memory location that doesn't seem to be set anywhere).</p>

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