~$ nc 127.0.0.1 9999 | mplayer -
MPlayer SVN-r38157 (C) 2000-2019 MPlayer Team
225 audio & 468 video codecs
do_connect: could not connect to socket
connect: No such file or directory
Failed to open LIRC support. You will not be able to use your remote control.

Playing -.
Reading from stdin...
libavformat version 58.45.100 (external)


Exiting... (End of file)