what is the difference between "./somescript.sh" and ". ./somescript.sh"

Posted by Peter on Stack Overflow See other posts from Stack Overflow or by Peter
Published on 2010-04-14T00:58:13Z Indexed on 2010/04/14 1:03 UTC
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linux

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shell

This question may sounds silly to you. Today I was following some instructions to install a software in Linux. There was a script that needs to be run first. It set some environment variables.

The instruction told me to execute . ./setup.sh, but I made a mistake by executing ./setup.sh. So the env was not set. Finally I noticed this and proceeded.

I want to know what exactly is the difference between both? I am completely new to Linux so please be as elaborate as possible.

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