> I encountered some problem: there is a trivial program on Go that > writes to the files / dev / eiaU4 / eiaUctl and / dev / eiaU the
I hope you meant /dev/eiaU4/eiaU, not /dev/eiaU Unless you do a "bind -a /dev/eiaU4 /dev" after starting the usb serial driver, which allows you to reference the device files as /dev/eiaUctl and /dev/eiaU and not have to remember the unit number.
