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Full Discussion: Does SH support indirect expansion like BASH?
Top Forums Shell Programming and Scripting Does SH support indirect expansion like BASH? Post 302529502 by dimentiy on Thursday 9th of June 2011 12:05:40 PM
Old 06-09-2011
Does SH support indirect expansion like BASH?
Hello,

is there a kind soul who can answer me, does the SH support double substitution known as indirect expansion similar to BASH? The syntax for bash is ${!var}.

For instance in bash I can write something like this:

Code:
VAR="value"
REF_VAR="VAR"
echo ${!REF_VAR}

and get the "value" output. Is there a way to acheive this in SH?

If no is there a workaround on it?

Thank you.
Last edited by radoulov; 06-09-2011 at 01:17 PM.. Reason: Code tags!
 

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LEARN ABOUT DEBIAN

shorewall-lite-vardir

SHOREWALL-LITE-VAR(5)						  [FIXME: manual]					     SHOREWALL-LITE-VAR(5)

NAME

       vardir - Shorewall Lite file

SYNOPSIS

       /etc/shorewall-lite/vardir

DESCRIPTION

       This file does not exist by default. You may create the file if you want to change the directory used by Shorewall Lite to store state
       information, including compiled firewall scripts. By default, the directory used is /var/lib/shorewall-lite/.

       The file contains a single variable assignment:

       VARDIR=directory

       where directory is the name of a directory. If you add this file, you should copy the files from /var/lib/shorewall-lite to the new
       directory before performing a shorewall-lite restart.

	   Note
	   Beginning with Shorewall 4.5.2, use of this file is deprecated in favor of specifying VARDIR in the shorewallrc file used during
	   installation of Shorewall Core. While the name of the variable remains VARDIR, the meaning is slightly different. When set in
	   shorewallrc, Shorewall Lite, will create a directory under the specified path name to hold state information.

	   Example:

	   VARDIR=/opt/var/lib/

	   The state directory for Shorewall Lite will be /opt/var/lib/shorewall-lite/.

	   When VARDIR is set in /etc/shorewall-lite/vardir, Shorewall Lite will save its state in the directory specified.

EXAMPLE

       VARDIR=/root/shorewall

FILES

       /etc/shorewall-lite/vardir

SEE ALSO

       shorewall(8), shorewall-accounting(5), shorewall-actions(5), shorewall-blacklist(5), shorewall-hosts(5), shorewall-interfaces(5),
       shorewall-ipsec(5), shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5), shorewall-netmap(5), shorewall-params(5),
       shorewall-policy(5), shorewall-providers(5), shorewall-proxyarp(5), shorewall-route_rules(5), shorewall-routestopped(5),
       shorewall-rules(5), shorewall.conf(5), shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tcrules(5), shorewall-tos(5),
       shorewall-tunnels(5), shorewall-zones(5)

[FIXME: source] 						    06/28/2012						     SHOREWALL-LITE-VAR(5)
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