sudo avrdude -p atmega328p -c dragon_isp -P usb -e -Uflash:w:foo.hex

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.15s

avrdude: Device signature = 0x1e950f
avrdude: erasing chip
avrdude: reading input file "event_serial.cpp.hex"
avrdude: input file event_serial.cpp.hex auto detected as Intel Hex
avrdude: writing flash (2388 bytes):

Writing | ################################################## | 100% 2.34s

avrdude: 2388 bytes of flash written
avrdude: verifying flash memory against event_serial.cpp.hex:
avrdude: load data flash data from input file event_serial.cpp.hex:
avrdude: input file event_serial.cpp.hex auto detected as Intel Hex
avrdude: input file event_serial.cpp.hex contains 2388 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 1.81s

avrdude: verifying ...
avrdude: 2388 bytes of flash verified

avrdude: safemode: Fuses OK

avrdude done.  Thank you.