Troubleshooting OSError: out of pty devices

python linux pty
kdt picture kdt · Dec 19, 2011 · Viewed 9.5k times · Source

From time to time I'm getting an OSError exception with the message 'out of pty devices' when calling pty.openpty() (it's happening when a bunch of instances of my scripts run concurrently).

What is the limit that I'm hitting? How can I get around this?

CentOS 5.6, Python 2.4

Answer

mirk picture mirk · Dec 19, 2011

In my Ubuntu Linux, the max number of open ptys is given by:

cat /proc/sys/kernel/pty/max

This value is configurable in: 

/etc/sysctl.conf

All this info, and much more can be found in:

man pty

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