/dev/desu

i would like to have /dev/desu on leenux, an "infinite" file that only outputs DESUDESUDESUDESUDESU etc. pp.

is it possible to create that via mkfifo ?

This better? Yes, I'm too lazy to test it.
mkfifo("/dev/desu",0644);
while(1) {
  int fd = open("/dev/desu", O_WRONLY);
  while(write(fd, "DESU", 4) > 0);
  close(fd);
}