• gdbserver

Usage: gdbserver [OPTIONS] COMM PROG [ARGS ...]

gdbserver [OPTIONS] --attach COMM PID

gdbserver [OPTIONS] --multi COMM

COMM may either be a tty device (for serial debugging), or 

HOST:PORT to listen for a TCP connection.

 gdbserver 127.0.0.1:1234

• gdb

 target remote 127.0.0.1:1234