====== Ever wanted to shutdown your workstation and... ======

Ever wanted to shutdown your workstation and confused some random $xterm with an ssh-session and one with a local shell? Still want to use your pretty shell color scheme on all your accounts anyway? Look no further.
After managing to shutdown the wrong machine once or twice a year I finally took the time to build some visual safeguards into my [[http://zsh.sourceforge.net/|ZSH]].

{{ :blog:2008:07:zshcolors.png |Colors, Yay}}

However, since both ssh sessions and X terminal emulators allocate the same kind of pseudo terminal
the best thing I came up with so far was iterating over the chain of parent processes until finding ''init'' or ''sshd''. If anyone got a cleaner solution for this problem please tell me ;-)

<code bash|.zshrc>
function ppid_of() {
	grep ^PPid /proc/$1/status | awk '{print $2}'
}

function is_ssh_login() {
	pid=$$

	while [ $pid != 1 ]; do
		if `grep -q sshd /proc/$pid/cmdline` ; then
			return 0
		fi
		pid=`ppid_of $pid`
	done

	return -1
}
</code>

<code bash|.zshrc>
## see console_codes(4) for number<->color relations
# red foreground
root_color=31
# green foreground
user_color=32
# blue foreground
cwd_color=34


if [ `id -u` == 0 ]; then
	hostname_color=$root_color
else
	hostname_color=$user_color
fi

if is_ssh_login ; then
	# background color = foreground color
	hostname_color=`expr $hostname_color + 10`
fi

PROMPT=`echo "%{\033[01;${hostname_color}m%}%n@%m%{\033[00m%}:%b%{\033[01;${cwd_color}m%}%~%{\033[00m%} %# "`
</code>

{{tag>sh zsh quick_and_dirty}}

~~DISCUSSION~~