What does export do in BASH?

Posted by Chas. Owens on Super User See other posts from Super User or by Chas. Owens
Published on 2010-06-16T20:02:37Z Indexed on 2010/06/16 20:13 UTC
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bash

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export

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shell-script

It is hard to admit, but I have never really understood what exactly export does to an environment variable. I know that if I don't export a variable I sometimes can't see it in child processes, but sometimes it seems like I can. What is really going on when I say

export foo=5

and when should I not export a variable?

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