Donovan Baarda wrote:
Consider the following. This is pretty much the only way you can use
popen2 reliably without knowing specific behaviours of the executed
command;
> ...
fcntl.fcntl(child_in, fcntl.F_SETFL, flags | os.O_NONBLOCK) # \
... # /
fcntl.fcntl(child_out, fcntl.F_SETFL, flags | os.O_NONBLOCK)# \
I still don't believe you need to make these non-blocking.
When select() returns a fd for reading/writing, it's telling
you that the next os.read/os.write call on it will not block.
Making the fd non-blocking as well is unnecessary and perhaps
even undesirable.
For 1) and 2), note that popen2 returns file objects, but as they cannot
be reliably used as file objects, we ignore them and grab their
fileno(). Why does popen2 return file objects if they cannot reliably be
used?
I would go along with giving file objects alternative read/write
methods which behave more like os.read/os.write, maybe called
something like readsome() and writesome(). That would eliminate
the need to extract and manipulate the fds, and might make it
possible to do some of this stuff in a more platform-independent
way.
--
Greg Ewing, Computer Science Dept, +--------------------------------------+
University of Canterbury, | A citizen of NewZealandCorp, a |
Christchurch, New Zealand | wholly-owned subsidiary of USA Inc. |
[EMAIL PROTECTED] +--------------------------------------+
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
