avrdude -v -p attiny85 -C /home/sergio/.platformio/packages/tool-avrdude/avrdude.conf -c stk500v1 -b 19200 -e -D -U flash:w:.pioenvs/a
ttiny/firmware.hex:i

avrdude: Version 6.3, compiled on Sep 12 2016 at 15:21:49
System wide configuration file is "/home/sergio/.platformio/packages/tool-avrdude/avrdude.conf"
/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)

Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

User configuration file is "/home/sergio/.avrduderc"
avrdude: ser_open(): can't set attributes for device "/dev/ttyS0": Inappropriate ioctl for device
avrdude done.  Thank you.
User configuration file does not exist or is not a regular file, skipping

Using Port                    : /dev/ttyS0
Using Programmer              : stk500v1
Overriding Baud Rate          : 19200