How to execute a scirpt in Linux

A shell script can be executed using the following syntax

chmod +x script.sh

./script.sh

You can also run the script directly without setting the script execute permission

bash script.sh

or
source script.sh
or

. script.sh

In the last example we are using . (dot) or source command which reads and executes commands from filename in the current shell.
When a script is executed using either the bash command or the source (.) command, you don't have to set execute permission on script.

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