[gentoo-user] 'if echo hello' in .bashrc

[Stroller]

Hi there,

I've just realised that grep hasn't been highlighting results in  
colour, and it occurred to me that I was sure it has supported this  
facility for some time. Thus I discovered the --colour=always flag to  
grep and trying to make this permanent I stumbled upon this site: http://www.ccs.neu.edu/home/katz/unix-colors.html

To find the part to which I refer you'll need to scroll down about  
halfway through that page to "Colorize grep"; the author advises adding:

   if echo hello|grep --color=auto l >/dev/null 2>&1; then
     export GREP_OPTIONS='--color=auto' GREP_COLOR='1;32'
   fi

to ~/.bashrc

Why does he echo hello, please?  Is this to ensure that the file is  
not sourced by a non-interactive shell, or by a script or something? I  
understood that that was the difference between .bashrc  
& .bash_profile, anyway - that "interactive commands" like colourising  
stuff should go in .bashrc, to use /usr/local/mount instead of the  
system on then one might alias that in .bash_profile.

It's early in the morning here, so obviously I'm not getting something.

Thanks in advance for any pointers,

Stroller.