[Python-Dev] PEP 446: Add new parameters to configure the inherance of files and for non-blocking sockets (original) (raw)

Charles-François Natali cf.natali at gmail.com
Sat Jul 6 11:23:26 CEST 2013

I've read your "Rejected Alternatives" more closely and Ulrich Drepper's article, though I think the article also supports adding a blocking (default True) parameter to open() and os.open(). If you try to change that default on a platform where it doesn't work, an exception should be raised.

Contrarily to close-on-exec, non-blocking only applies to a limited type of files (e.g. it doesn't work for regular files, which represent 90% of open() use cases).

Also, one of the main reasons for exposing close-on-exec in open()/socket() etc is to make it possible to create file descriptors with the close-on-exec flag atomically, to prevent unwanted FD inheritance especially in multi-threaded code. And that's not necessary for the non-blocking parameter.

Those are two reasons why IMO "blocking" doesn't have to receive the same treatment as close-on-exec (there's also the Windows issue but I'm not familiar with it).

cf

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