From mboxrd@z Thu Jan  1 00:00:00 1970
From: lyndon@orthanc.ca (Lyndon Nerenberg)
Date: Tue, 18 Apr 2017 17:50:05 -0700
Subject: [TUHS] Bourne shell and comments
In-Reply-To: <020a01d2b885$94bd49c0$be37dd40$@ronnatalie.com>
References: <20170418204834.GA22198@minnie.tuhs.org>
 <020a01d2b885$94bd49c0$be37dd40$@ronnatalie.com>
Message-ID: <DBD26EB7-FFAE-472F-9C71-27ECAC2A085E@orthanc.ca>

> Ron said:

> I still remember using : for a comment in the V6 shell.   Was also the label
> for goto.

What's cool about ':' vs. '#' is:

-----8<-----8<-----8<-----8<-----8<-----8<-----

function cd {
        command cd "$@" && setprompt
}

function setprompt {
        PS1=": "`id -un`@`hostname|sed 's;\..*$;;'`:'${PWD}; '; export PS1
}

setprompt

-----8<-----8<-----8<-----8<-----8<-----8<-----

Stick that in your .env and you get a snarf-and-barf'able shell prompt that evals as a noop.  Blatantly ripped off from plan9port IIRC.  I run this across all manner of *BSD and Solaris and Linux and it just works.

--lyndon