Serial device name for PTT too short (again)

[oe1rsa]

In file audio.h the field ptt_device is reserved with 100 char's. The comment already mentions it:

/* For years, 20 characters was plenty then we start getting extreme names like this: */
/* /dev/serial/by-id/usb-FTDI_Navigator__CAT___2nd_PTT__00000000-if00-port0 */

My dev name is:

/dev/serial/by-id/usb-Silicon_Labs_CP2102_USB_to_UART_Bridge_Controller_IC-9100_04002076_A-if00-port0

This is 102 chars. Not sure what the best solution would be. One option is to include limits.h and use PATH_MAX. I am afraid this will rise portability issues. I guess the best option would be dynamic allocation (with the burden of freeing it later). I would ask if someone can make it 200 chars (or 256) at least.