[Discuss] rsync v. cp in data migration

Derek Martin invalid at pizzashack.org
Sat May 25 11:42:10 EDT 2013


One last point:

On Sat, May 25, 2013 at 09:32:02AM -0400, Greg Rundlett (freephile) wrote:
> # we will use a prepared file 'users' whose contents are a list of users,
> one user per line
> while read USER

The variable $USER is set for you by the system when you log in, and
some things may depend on it (this is a very old Unix feature, and
I've forgotten which--most things should no longer do this, for the
reason I'm describing now).  If you change the value of $USER, any
such things may break.  Generally the convention is to use upper case
names for environment variables (i.e. things you want to have
persistence across sessions/processes/etc.), and shell scripts should
use lower case names for their variables to avoid unintended conflicts
like this.

-- 
Derek D. Martin    http://www.pizzashack.org/   GPG Key ID: 0xDFBEAD02
-=-=-=-=-
This message is posted from an invalid address.  Replying to it will result in
undeliverable mail due to spam prevention.  Sorry for the inconvenience.



More information about the Discuss mailing list