tee_splice_vmsplice https://linux.die.net/man/2/tee https://linux.die.net/man/2/splice https://linux.die.net/man/2/vmsplice http://www.tutorialspoint.com/unix_system_calls/vmsplice.htm http://man7.org/linux/man-pages/man2/open.2.html This is how it runs: # date |./a.out test | cat