Re: [Boost-users] asio error codes

Subject: Re: [Boost-users] asio error codes
From: Christopher Pisz (cpisz_at_[hidden])
Date: 2011-10-04 18:30:51

Igor R <boost.lists <at> gmail.com> writes:

> 
> > I don't see in the documentation anything that says which error code could
> > result from the various asynchronous calls.
> >
> > Obviously, I would have to identify all connection related error codes and 
set
> > the state of my process such that a reconnect was the way to handle it. In
> > some cases a retry might be needed. However, I don't see a way to get a 
list
> > of the possible error codes that need to get checked for aside from hours 
and
> > hours of debugging trial and error.
> >
> > Does there exist somewhere a list of error codes that could result from
> > async_read? which would I get from async_write?, async_accept? etc..etc.
> >
> > I see it is a sytem::error_code, and I can look at the header, I can even 
find
> > a doc that lists all of them and see asio has a group, but I can't tell 
which might occur when.
> 
> Most of error_code values come from the lower levels and they are just
> translated/propagated by asio to your application, so the error you
> get is not even platform-independent, i.e. on some platform you can
> get one error, while in the same situation on another platform you
> might get another error.
> But does it really affect states in your progam? Why is it important
> for your state-machine whether you get 10053, 10054 or 10060 error
> code?
> 

Well, my main concern is for reads and writes over tcp. Determining if my 
connection has been dropped or is unrecoverable, or if I should retry the read 
or write.

I see lots of 'no so self explanatory' error codes in the list of possibles. 
Such as, 
"Operation already in progress"
"access_denied"
"operation_aborted"

knowing when and why these occur dictates how I would handle them and whether 
I'd give up or retry.