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Re: /etc/shells management

On 08-Sep-03, 03:42 (CDT), Branden Robinson <branden@debian.org> wrote: 
> I personally stongly advocate -n and -z over [ "$var" ] and really
> horrible tests like:
> if [ "x$var" = "x" ]
> and
> if [ "x$var" != "x" ]
> Those just strike me as obscurantist (which might explain why they
> feature prominently in shell scripts by Ian Jackson, heh).

Probably because Ian learned shell scripting in the days (or from
scripts written in those days) when

   [ "$var" = "foo" ] 

was likely to cause problems when $var was undefined. So we learned to do

   [ "X$var" = "Xfoo" ]

which leads to using '[ "X$foo" = "X" ]' to test for empty.


Steve Greenland
    The irony is that Bill Gates claims to be making a stable operating
    system and Linus Torvalds claims to be trying to take over the
    world.       -- seen on the net

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