Cloud functions work much the same way as cloud actions, except that they don't perform an operation on a specific instance, and so do not need a machine name to be specified. However, since they perform an operation on a specific cloud provider, that provider must be specified.
$ salt-cloud -f show_image ec2 image=ami-fd20ad94
Docs for previous releases are available on salt.rtfd.org.
Latest Salt release: 2014.1.13
Try the shiny new release candidate of Salt, v2014.7.0rc6! More info here.
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