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Top Forums Shell Programming and Scripting Using the value of one variable to name another variable (in bash) Post 302326621 by DeCoTwc on Thursday 18th of June 2009 10:00:57 AM
Old 06-18-2009
Quote:
Originally Posted by otheus
Well, you're using bash, and that has support for arrays (although older versions might not). Second, you can create variables using eval:
Code:
let x=10
eval x_$x=12
set|grep ^x

I appreciate the thought. I understand the idea of arrays, but I'm not really at the point where I can use them.

I'm trying to understand the eval command, but I'm not sure I'm getting it. I read through the man page and some examples on line...but it's not sinking in. But I've been up all night doing a maintenance, so I doubt I could understand much of anything right now.
 

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ENVSTORE(1)						    BSD General Commands Manual 					       ENVSTORE(1)

NAME
envstore -- save and restore environment variables SYNOPSIS
envstore command [args ...] DESCRIPTION
envstore can save and restore environment variables, thus transferring them between different shells. command must be one of clear Forget all stored variables eval Produce shell code for evaluation, restoring all saved variables list List saved variables in better readable format save variable [value] Save variable either with its current shell value or with value rm variable Remove variable from store Note: Only the first character of command is checked, so envstore e instead of envstore eval, envstore c for envstore clear, etc., are also valid. ENVIRONMENT
ENVSTORE_FILE The file in which the environment parameters are stored, /tmp/envstore-EUID by default, LIMITATIONS
Variable names or values must not contain null bytes or newlines. Due to limitations imposed by most shells, it is not possible to save parameters containing more than one consecutive whitespace. envstore will save and display them correctly, but unless you do IFS trickery, your shell will not be able to load them. The current maximum length (in bytes) is 255 bytes for the variable name and 1023 bytes for its content. AUTHOR
envstore was written by Daniel Friesel <derf@derf.homelinux.org>. Original idea and script by Maximilian Gass <mxey@ghosthacking.net>. SEE ALSO
envify(1) BSD
December 1, 2009 BSD
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