bash - How to check if docker machine exists programmatically? -

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i'm using docker-machine manage cloud servers. i'm writing bash scripts automate tasks. question is: "how check in bash script if docker machine specific name exists?". need expression return true if exists , false if doesn't.

thanks

just run through grep, if regexp enough you. example if have machine called foo:

$ docker-machine ls -q | grep '^foo$'

should work , return 0. caret matches start of line , space avoids partial matches. if doesn't match non-zero return code.


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