Michael Trimarchi wrote:
Hi,

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.

Init starts your mux. The mux starts and gets interrupted. init knows mux is up and starts rild. mux hasn't set property yet. rild runs and looks at property which isn't set. This is a race condition. Doesn't always happen like that but it can. You cannot control it with the status. That property isn't set by your mux. It is set by init. Maybe you can have another property of your own you set that init keys off. I'm not sure if init is monitoring all property settings or not. But the property has to be set after the ptmx call and the rild property has been set. Otherwise you cannot be certain it is set before rild starts.

It still doesn't solve the issue of recovery if rild closes the pts. I'm pretty sure it will be invalid after that.


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