If you run a command via ssh (secure shell) on linux and you get the following output:
stdin: is not a tty
The most common cause is the `mesg y` or similar command found in the file:
/etc/bashrc
###What is mesg ?
> mesg is a Unix command that sets or reports the permission other users have to write to your terminal using the talk and write commands.
###How can I fix this issue?
Option 1 would be to comment out the line.
Option 2 would be to change the line to something like this to only invoke the command when you are actually using a connection with `tty`:
if tty -s; then mesg y; fi