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Full Discussion: Indirect variables in Bash
Top Forums Shell Programming and Scripting Indirect variables in Bash Post 302769197 by Corona688 on Monday 11th of February 2013 12:51:12 PM
Old 02-11-2013
Kind of exactly how I've shown you.

Code:
A="abc"
B="def"

read $A$B <<<"string"

...should put the string "string" into the variable named abcdef.

This is how it's often used:
Code:
read VARNAME

...but note that it takes a variable name -- a string -- not the variable itself. You can feed it whatever string you please, derived from whatever variables you please, and do things that would otherwise require ugly insecure eval hacks.

You can redirect into it any way you please. <<< is an ordinary redirection in BASH which replaces stdin with a string.
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BASHBUG(1)						      General Commands Manual							BASHBUG(1)

NAME
bashbug - report a bug in bash SYNOPSIS
bashbug [--version] [--help] [email-address] DESCRIPTION
bashbug is a shell script to help the user compose and mail bug reports concerning bash in a standard format. bashbug invokes the editor specified by the environment variable EDITOR on a temporary copy of the bug report format outline. The user must fill in the appropriate fields and exit the editor. bashbug then mails the completed report to bug-bash@gnu.org, or email-address. If the report cannot be mailed, it is saved in the file dead.bashbug in the invoking user's home directory. The bug report format outline consists of several sections. The first section provides information about the machine, operating system, the bash version, and the compilation environment. The second section should be filled in with a description of the bug. The third sec- tion should be a description of how to reproduce the bug. The optional fourth section is for a proposed fix. Fixes are encouraged. ENVIRONMENT
bashbug will utilize the following environment variables if they exist: EDITOR Specifies the preferred editor. If EDITOR is not set, bashbug defaults to emacs. HOME Directory in which the failed bug report is saved if the mail fails. TMPDIR Directory in which to create temporary files and directories. SEE ALSO
bash(1) AUTHORS
Brian Fox, Free Software Foundation bfox@gnu.org Chet Ramey, Case Western Reserve University chet@po.cwru.edu GNU Bash-4.0 1998 July 30 BASHBUG(1)
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