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Full Discussion: Eval
Top Forums Shell Programming and Scripting Eval Post 302798505 by Corona688 on Wednesday 24th of April 2013 03:12:10 PM
Old 04-24-2013
Quote:
Originally Posted by rbatte1
I feel such a fool. Fortunately, I only use it to get an indirect variable
In BASH, you can get an indirect variable via
Code:
NAME="VAR"
VAR="ASDF"
echo "${!VAR}"

This is a bash-only feature sadly, I used to think ksh93 had it too..

Quote:
...or scheduled tasks reading in assignments from a parameter file that I control, which is a pretty rare need in itself.
You can set arbitrary variable names with the read builtin, which will work in any shell. This trick works because read takes a variable name, not the variable itself.

Code:
VARNAME="ASDF"
read $VARNAME <<EOF
this contents get assigned to asdf
EOF

echo $ASDF

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GIT-VAR(1)							    Git Manual								GIT-VAR(1)

NAME
git-var - Show a Git logical variable SYNOPSIS
git var ( -l | <variable> ) DESCRIPTION
Prints a Git logical variable. OPTIONS
-l Cause the logical variables to be listed. In addition, all the variables of the Git configuration file .git/config are listed as well. (However, the configuration variables listing functionality is deprecated in favor of git config -l.) EXAMPLE
$ git var GIT_AUTHOR_IDENT Eric W. Biederman <ebiederm@lnxi.com> 1121223278 -0600 VARIABLES
GIT_AUTHOR_IDENT The author of a piece of code. GIT_COMMITTER_IDENT The person who put a piece of code into Git. GIT_EDITOR Text editor for use by Git commands. The value is meant to be interpreted by the shell when it is used. Examples: ~/bin/vi, $SOME_ENVIRONMENT_VARIABLE, "C:Program FilesVimgvim.exe" --nofork. The order of preference is the $GIT_EDITOR environment variable, then core.editor configuration, then $VISUAL, then $EDITOR, and then the default chosen at compile time, which is usually vi. GIT_PAGER Text viewer for use by Git commands (e.g., less). The value is meant to be interpreted by the shell. The order of preference is the $GIT_PAGER environment variable, then core.pager configuration, then $PAGER, and then the default chosen at compile time (usually less). SEE ALSO
git-commit-tree(1) git-tag(1) git-config(1) GIT
Part of the git(1) suite Git 1.8.5.3 01/14/2014 GIT-VAR(1)
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