A read-only tmux session for demos and remote debugging

public-tmux

#!/bin/sh
# To be used with something like this in sshd_config:
#
# Match User public-tmux
#     X11Forwarding no
#     AllowTcpForwarding no
#     PasswordAuthentication yes
#     ForceCommand /usr/bin/tmux -S /tmp/public-tmux-socket attach -r -t public
#

SOCKET=/tmp/public-tmux-socket
if tmux -S $SOCKET list-sessions 2>/dev/null | grep -q ""; then
        echo "The socket at $SOCKET already has sessions, attaching..."
        exec tmux -S $SOCKET attach -t public
else
        echo "Creating a new tmux session with socket at $SOCKET and changing it to be world-writeable..."
        exec tmux -S $SOCKET new-session -s public "chmod o=w $SOCKET; $SHELL"
fi