Generates a string which is the pathname for the current controlling terminal for the process. On error this will set errno, which can be checked using posix_get_last_error()
Upon successful completion, returns string of the pathname to
the current controlling terminal. Otherwise
FALSE is returned and errno
is set, which can be checked with posix_get_last_error().
This example will display the path to the current TTY.
echo "I am running from ".posix_ctermid();