spawnProcess should reset signal handlers to default before exec()ing new executable

New submission from itamarst <[email protected]>:

Python (and presumably applications) override certain signals, in particular SIGPIPE; spawnProcessed processes will have SIGPIPE in a state they don't necessarily expect. We should reset signal handlers to their default before calling exec().

Ticket #4159 would allow this, but that still requires users to figure out they need to do this. It would be better to have good defaults and documented behavior.

See http://bugs.python.org/issue1652 for a detailed write-up of Python's perspective on the issue.

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Type     : enhancement
Component: core
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/4199