Variable var names

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From	Frank Winkler <usenet@f.winkler-ka.de>
Newsgroups	comp.unix.shell
Subject	Variable var names
Date	Fri, 12 Jun 2026 09:30:16 +0200
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Hi there !

I'm playing with the following in an interactive bash as well as in a 
ksh script:

$ n=1
$ x1="  ok  "
$ x2="  not ok  "
$ eval echo \$x$n
ok
$ eval echo "\$x$n"
ok
$ n=2
$ eval echo "\$x$n"
not ok
$

So the variable var name seems to work but why are the blanks "deleted" 
here? I also tried some variants with "printf", but also with no success.

Just out of curiosity, I tried this:

$ IFS="" eval echo ".\$x$n."
.  not ok  .
$

To my surprise, it works but why is IFS relevant here? And to my even 
bigger surprise, it looks like everything seems to behave as expected in 
the bash session but in the ksh script, IFS is not just changed for this 
single command but globally - so I had to save and restore it to prevent 
the whole script from exploding. This makes the interesting part much 
longer and more complicated, eating up the potential advantage and 
coolness superiority over just doing something like

   [ $n -eq 1 ] && echo "$x1"
   [ $n -eq 2 ] && echo "$x2"

Any hints from the experts?

TIA

	Frank

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Thread

Variable var names Frank Winkler <usenet@f.winkler-ka.de> - 2026-06-12 09:30 +0200
  Re: Variable var names gazelle@shell.xmission.com (Kenny McCormack) - 2026-06-12 09:02 +0000
    Re: Variable var names Frank Winkler <usenet@f.winkler-ka.de> - 2026-06-13 12:29 +0200
      Re: Variable var names gazelle@shell.xmission.com (Kenny McCormack) - 2026-06-13 11:14 +0000
      Re: Variable var names Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-13 13:15 +0200
  Re: Variable var names ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-12 11:26 +0000
    Re: Variable var names ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-12 11:38 +0000
      Re: Variable var names Frank Winkler <usenet@f.winkler-ka.de> - 2026-06-12 14:07 +0200
        Re: Variable var names ram@zedat.fu-berlin.de (Stefan Ram) - 2026-06-12 12:31 +0000
          Re: Variable var names Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-13 02:48 +0000
  Re: Variable var names Christian Weisgerber <naddy@mips.inka.de> - 2026-06-12 12:12 +0000
    Re: Variable var names Frank Winkler <usenet@f.winkler-ka.de> - 2026-06-12 15:19 +0200
    Re: Variable var names Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-13 02:51 +0000
  Re: Variable var names Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2026-06-12 13:42 +0100
  Re: Variable var names Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-12 17:41 +0200
    Re: Variable var names Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2026-06-12 17:54 +0200
    Re: Variable var names Frank Winkler <usenet@f.winkler-ka.de> - 2026-06-13 12:32 +0200
      Re: Variable var names Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-14 01:12 +0000
  Re: Variable var names Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-06-13 00:20 +0000
  Re: Variable var names Kaz Kylheku <046-301-5902@kylheku.com> - 2026-06-23 21:25 +0000
    Re: Variable var names Helmut Waitzmann <nn.throttle@erine.email> - 2026-06-24 10:45 +0200
    Re: Variable var names Christian Weisgerber <naddy@mips.inka.de> - 2026-06-24 11:41 +0000

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