Michael Trimarchi trimarchi at
Fri Feb 13 14:49:02 CET 2009


Sean McNeil wrote:
> Michael Trimarchi wrote:
>> Hi,
>> Sean McNeil wrote:
>>> Michael Trimarchi wrote:
>>>> Hi,
>>>> Sean McNeil wrote:
>>>>> Hi Michael,
>>>>> This is a very bad idea for several reasons:
>>>>> 1) You cannot guarantee which pts you get.
>>>> Yes I can, it is just a script property.
>>> No you can't. You do not know that something else is using pts or 
>>> not. You cannot guarantee that you will get /dev/pts/0 when you 
>>> first open /dev/ptmx. Also there is a startup race condition. You 
>>> have to know that the mux daemon is up and has allocated the pts 
>>> before you can possibly pass it to the rild. The OM stack uses dbus 
>>> to get around that. The pts isn't allocated until needed and then 
>>> the actual device is passed back. It doesn't sound like you are 
>>> doing that and rild isn't setup to use dbus. If you bundle it into a 
>>> script you still have possible race conditions. Plus if the script 
>>> dies, then you need to make sure processes are not still around (mux 
>>> and ril) before you try to start up again. It just makes things a 
>>> lot more complicated when it doesn't need to be.
>> This is can be done by a property setting
>> on property:vchanneld.status=start
>>    start ril-daemon
>> You can give the serial device to the rild setting property.
> Again, no. You cannot guarantee that the property will be set before 
> the rild gets started. This is a race condition. Also, when/if the 
> rild aborts then the pts will no longer be available as it gets 
> closed. You'll never be able to talk to the modem again.
The rild start disable. The vchanneld start and initialize the pts, then 
it prepare the rild
enviroment and set its status to start. The init process take the 
enviroment variable and see that
it's change and start the rild. The rild open the pseudo terminal and it 
has no problem.


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