setting variable with unknown name in bash

Question

I would like to set a variable which name is stored in a file (is an output of a sed executed earlier)

the file would look like:
py1
so setting our variable would be like: set cat file=value
but echoing $py1 gives me nothing.

Is that possible with bash version 2.05?

kurumi · Accepted Answer · 2011-02-16 15:13:18Z

3

This is the "preferred" way to do it (bash) without using cat or eval

declare $(<file)=value

answered Feb 16, 2011 at 15:13

kurumi

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1 Comment

well bash gives me this: declare: Command not found. so i guess i have to use eval

Eugene Yarmash · Accepted Answer · 2011-02-16 15:21:43Z

2

Use eval:

eval "$(cat file)=value"

Update: The command substitution $(cat file) can be replaced by the equivalent but faster $(< file).

answered Feb 16, 2011 at 14:57

Eugene Yarmash

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Yeah, that was simple... haven't heared before 'bout that eval (evil :)) function!Thanks

Paul Creasey · Accepted Answer · 2011-02-16 14:58:10Z

0

You'll need to use eval

eval $(cat file)=value

answered Feb 16, 2011 at 14:58

Paul Creasey

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