Changes between Version 46 and Version 47 of FrequentlyAskedQuestions


Ignore:
Timestamp:
02/15/12 22:03:52 (10 years ago)
Author:
Jean-Paul Calderone
Comment:

It was no longer the previous answer.

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  • FrequentlyAskedQuestions

    v46 v47  
    202202[http://twistedmatrix.com/documents/current/api/twisted.internet.interfaces.IReactorProcess.spawnProcess.html spawnProcess] defaults to clearing the environment of child processes as a security feature. You can either provide a dictionary with exactly the name-value pairs you want the child to use, or you can simply pass in {{{os.environ}}} to inherit the complete environment.
    203203
    204 === My Deferred or !DeferredList never fires, so my program just mysteriously hangs! What's wrong? ===
     204=== My exceptions and tracebacks aren't getting printed!  Or My Deferred or !DeferredList never fires, so my program just mysteriously hangs! What's wrong? ===
    205205
    206206It really depends on what your program is doing, but the most common cause is this: it is firing -- but it's an error, not a success, and you have forgotten to add an [http://twistedmatrix.com/documents/current/core/howto/glossary.html#errback errback], so nothing happens. Always add errbacks!
     
    216216
    217217If your program appears to send messages as expected, it might be possible that the sending program is working as expected but the receiving program is buffering the messages. Eg: your messages are buffered by a web browser, and you don't close your message. Use telnet instead. Especially as a beginner, never forget that you can only see messages indirectly through the eyes of another program. Check your receiving program!
    218 
    219 === My exceptions and tracebacks aren't getting printed! ===
    220 
    221 See previous question.
    222218
    223219=== How do I use Deferreds to make my blocking code non-blocking? ===