Checking in and out

CARMA provides a generic interface across various SCMs, each of which may handle operations differently. Since it is not possible to predict whether the check in or check out operation for any given SCM will respectively expect or return a member's contents, CARMA has been designed such that the check in and check out actions are flag-setting operations. That is, no member contents are passed to or returned from the SCM as part of the check in and check out actions.

Certain SCMs might expect the contents of a member to be passed in during a check in operation for that member. A RAM for such an SCM should handle this case by storing the member contents in a temporary location before making the check in call to the SCM.

Similarly, certain SCMs might return the contents of a member during a check out operation for that member. A RAM for such an SCM should handle this case by storing the member contents in a temporary location until the client retrieves the contents.