regex - What does this BASH shell script excerpt do? -

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can explain following code please (assume host contains string):

host=${host//$'\n'/}

if above line declared inside function, variable "host" available other functions in same script?

according substring replacement subchapter abs guide:

host=${host//$'\n'/}

removes all occurrences of newline character $'\n' in host variable.

if above line declared inside function, variable host available other functions in same script?

yes, assuming host wasn't declared using bash local keyword.


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