[asterisk-bugs] [Asterisk 0018509]: [patch] Sending out unnecessary PROCEEDING messages breaks overlap dialing

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=18509 
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Reported By:                wimpy
Assigned To:                
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Project:                    Asterisk
Issue ID:                   18509
Category:                   Channels/chan_dahdi
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     feedback
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2010-12-21 02:30 CST
Last Modified:              2010-12-21 18:04 CST
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Summary:                    [patch] Sending out unnecessary PROCEEDING messages
breaks overlap dialing
Description: 
chan_dahdi sends out a PROCEEDING message as soon as a call has a match in
the dialplan.
I think sending this message is unnecessary and can be harmful.
I think it should only be sent when Dial() is called with a definitive
destination.

So far I thought chan_dahdi was unable to do outgoing overlap dialing, but
I just found out that it does, but sabotages itself.

If you have an
exten => _N!,1,Dial(dahdi/g1/${EXTEN})
and use overlap dialing, the trouble is that you get a PROCEEDING after
you dialed the first digit which will tell the phone that dialing has
finished.

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Relationships       ID      Summary
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related to          0016789 [patch] Overlap receiving timeout, plus...
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 (0129858) wimpy (reporter) - 2010-12-21 18:04
 https://issues.asterisk.org/view.php?id=18509#c129858 
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I think the trouble is not in the dialplan matching, but in the fact that a
PROCEEDING is sent at all at that point.
I think optimally it should only be sent when either Dial has a definite
peer or received a PROCEEDING itself, or when a playback with noanswer is
started.
(In the later case I wouldn't see an issue if it had to be done manually
via an explicit Proceeding() in the dialplan.)
In other cases an immediate CONNECT or DISCONNECT makes more sense. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-12-21 18:04 wimpy          Note Added: 0129858                          
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