[d]ets:lookup misbehaves when called during init:start?

Chris Pressey <>
Fri Apr 12 19:45:15 CEST 2002


Unhappy to report - this is not a consistent solution :(

Sometimes it works; other times, I can call inet_db:start/0, wait for a
process with the name inet_db to be registered, and sleep for a whole
extra second - and the problem is still there - all calls to
gen_tcp:accept/1 immediately return {error, closed}.

It is possibly a FreeBSD thing - I'm running 4.5-stable and "stable" can
be something of a euphemism in FreeBSDtalk :)

So, back to echo 'myapp:start().' | erl, for now...

Chris

On Tue, 02 Apr 2002 18:39:17 -0600
Chris Pressey <> wrote:

> Thanks!  FWIW, erl -run inet_db -run yourapp also seems to work.
> 
> Chris
> 
> On Mon, 01 Apr 2002 08:43:40 +0100
> Per Bergqvist <> wrote:
> 
> > Hi Chris,                                                             
> >                                                                       
> > the problem is that the inet_db modules has not yet been started      
> > and hence the inet_db ets table does not exist (yet).                 
> > It is supposed to be started by the kernel_sup supervisor.            
> >                                                                       
> > I haven't managed to recreate the problem with R8B-0 under            
> > Linux but two possible other workarounds are                          
> > a) wait for the inet_db process to become registered.                 
> > b) call inet_db:start from your application (as ftp,httpd and orber   
> > already does (for the same reason ?)).                                
> >                                                                       
> > /Per                                                                  
> >                                                                       
> > > I have discovered one workaround for this, although it comes at a   
> > grave                                                                 
> > > cost (namely, the use of the shell)                                 
> > >                                                                     
> > > Instead of                                                          
> > >                                                                     
> > >   erl -run module function                                          
> > >                                                                     
> > > use                                                                 
> > >                                                                     
> > >   echo 'module:function().' | erl                                   
> > >                                                                     
> > > Should have been obvious I suppose :)                               
> > >                                                                     
> > > Chris                                                               
> > >                                                                     
> > > On Fri, 29 Mar 2002 06:27:22 -0600                                  
> > > Chris Pressey <> wrote:                       
> > >                                                                     
> > > > I'd really like to get to the bottom of this one...               
> > > >                                                                   
> > > > I have a server that opens a socket.  If I start this server from 
> > the                                                                   
> > > > Erlang shell, everything works smoothly.  If I try to start it    
> > with a                                                                
> > > > -run command line argument to erl, it does *not* work and I get   
> > the                                                                   
> > > > following error message upon quitting:                            
> > > >                                                                   
> > > > {error_logger,{{2002,3,29},{6,10,40}},'Error in process           
> > <0.24481.0>                                                           
> > > > with exit value: {badarg,[{ets,lookup,[inet_db,tcp_module]},      
> > > > {inet_db,db_get,1},{gen_tcp,listen,2},{ce_socket,start,4}]}\n',[]}
> > > >                                                                   
> > > > I get the same error if I try to start it from my .erlang file.   
> > > >                                                                   
> > > > The question is... why?                                           
> > > >                                                                   
> > > > I've asked this once before a while ago, but got no response so   
> > far.                                                                  
> > > >                                                                   
> > > > It seems someone else is (anonymously) getting a very similar     
> > error                                                                 
> > > > trying to start the wiki in the same way:                         
> > > >                                                                   
> > > > http://www.bluetail.com/wiki/showPage?node=WikiSetup              
> > > >                                                                   
> > > > {badarg,[{ets,lookup_element,[dets_registry,wikie,3]},            
> > > >                     {dets,lookup,2},                              
> > > >                     {wikie,fetch_page,1},                         
> > > >                     {erl_eval,expr,3},                            
> > > >                     {erl_eval,exprs,4},                           
> > > >                     {esp,eval,2},                                 
> > > >                     {esp,expand,3},                               
> > > >                     {esp,do_expand_file,2},                       
> > > >                     {esp,handle,1}|                               
> > > >                     more]}                                        
> > > >                                                                   
> > > > Any information on this anomaly (e.g. why it happens and/or how to
> > work                                                                  
> > > > around it) would be greatly appreciated (seeing as I *really*     
> > don't want                                                            
> > > > to have to start my server from the Erlang shell every time I want
> > to                                                                    
> > > > use it :)                                                         
> > > >                                                                   
> > > > Thanks in advance,                                                
> > > > Chris                                                             
> > >                                                                     
> > =========================================================             
> > Per Bergqvist                                                         
> > Synapse Systems AB                                                    
> > Phone: +46 709 686 685                                                
> > Email:                                                    



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