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Full Discussion: How to evaluate a variable name on LHS of expression?
Top Forums Shell Programming and Scripting How to evaluate a variable name on LHS of expression? Post 302886803 by Perderabo on Monday 3rd of February 2014 05:31:46 PM
Old 02-03-2014
The OP mentioned ksh. If this is ksh93 or better there is another option called "name reference".
Code:
$ cat nameref
#! /bin/ksh

typeset -n z=a

a="alpha"
b="beta"
echo $z

z=b   # z is no longer a name reference
echo now $z

typeset -n z=b
echo finally $z
exit 0
$
$
$ ./nameref
alpha
now b
finally beta
$

However this won't work with ksh88 which is what many unix systems have.
 

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LEARN ABOUT DEBIAN

sysstat

SYSSTAT(5)							Linux User's Manual							SYSSTAT(5)

NAME

       sysstat - sysstat configuration file.

DESCRIPTION

       This  file is read by sa1(8) and sa2(8) shell scripts from the sysstat's set of tools.  It consists of a sequence of shell variable assign-
       ments used to configure sysstat logging.  The variables and their meanings are:

       HISTORY
	      The number of days during which a daily data file or a report should be kept. Data files or reports older than this number  of  days
	      will be removed by the sa2(8) shell script.

       COMPRESSAFTER
	      Number of days after which daily data files are to be compressed, either by gzip or bzip2.

       SADC_OPTIONS
	      Options  that  should be passed to sadc(8).  With these options (see sadc(8) manual page), you can select some additional data which
	      are going to be saved in daily data files.  These options are used only when a new data file is created. They will be  ignored  with
	      an already existing one.

FILES

       /etc/sysstat/sysstat

AUTHOR

       Sebastien Godard (sysstat <at> orange.fr)

SEE ALSO

       sadc(8), sa1(8), sa2(8)

       http://pagesperso-orange.fr/sebastien.godard/

Linux								  SEPTEMBER 2010							SYSSTAT(5)
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