how to exit command without using ctrl + d

Question

I want to open three terminals and I want to write a command in the first window that will send a Hello message to the other two. The command must allow a one-time sending without a response from the other terminals.

I used:

tee > /dev/pts/1 /dev/pts/2

and everything is good, but I want to exit the command after typing Hello without using Ctrl+d

Answer 1

To exit, tee needs an end-of-file. If you type normally, Ctrl+d provides this end-of-file. There are other ways:

echo "Hello" |tee > /dev/pts/1 /dev/pts/2 

provides the EOF after the "Hello".

head -1 |tee > /dev/pts/1 /dev/pts/2

provides the EOF after the first line.