On Mon, 25 Sep 2017 15:01:13 +0200 Ulf Samuelsson <[email protected]> wrote:
> Trying to open /dev/ttyUSB from a kernel driver (which works), but > locking the > serial port so noone else can access it does not work. > Any advice would be appreciated. File locks are advisory only. For the rest of it you might want to take a look at how the gsm mux driver works (the protocol stuff is scary but you can ignore that end). It plugs a line discipline into a tty and that muxes out as a collection of ttys and shows how it's meant to be done. That also means you have an owning process with the port open that can do locking on it and/or route any raw read/writes to the master port into the bit bucket. Alan
