-k is a local security hole

[tkorvola]

argv is public information on Unix systems: if pyro4-ns is started with the -k option, any local user can see the key with ps. Reading the key from a file would be more secure. For extra security, check that the key file is accessible only by the current user.

[irmen]

thank you, I'll think about a better implementation
@tkorvola what about reading it from an environment variable?

[tkorvola]

Not totally sure about environment variables, but probably safe.

[irmen]

Note that using 2-way SSL is the better alternative if you're concerned about security anyway.

I think I will be marking the use of the -k command line option a run time deprecation warning as well