Traditionally, write access is allowed by default. However, as users become more conscious of various security risks, there is a trend to remove write access by default, at least for the primary login shell. To make sure your ttys are set the way you want them to be set, mesg should be executed in your login scripts.
The mesg utility silently exits with error status 2 if the current standard error output does not refer to the terminal. In this case execute mesg is pointless. The command line option --verbose forces mesg to print a warning in this situation. This behaviour has been introduced in version 2.33.
- Disallow messages.
- Allow messages to be displayed.
If no arguments are given, mesg shows the current message status on standard error output.
- -v, --verbose
- Explain what is being done.
- -V, --version
- Display version information and exit.
- -h, --help
- Display help text and exit.
- Messages are allowed.
- Messages are not allowed.
- An error has occurred.